Technical Gyan

Windows

2021-07-08T12:19:00.003+05:30

What is Windows?

Windows is a graphical operating system developed by Microsoft. It allows users to view and store files, run the software, play games, watch videos, and provides a way to connect to the internet. It was released for both home computing and professional works.

Microsoft introduced the first version as 1.0

It was released for both home computing and professional functions of Windows on 10 November 1983. Later, it was released on many versions of Windows as well as the current version, Windows 10.

In 1993, the first business-oriented version of Windows was released, which is known as Windows NT 3.1. Then it introduced the next versions, Windows 3.5, 4/0, and Windows 2000. When the XP Windows was released by Microsoft in 2001, the company designed its various versions for a personal and business environment. It was designed based on standard x86 hardware, like Intel and AMD processor. Accordingly, it can run on different brands of hardware, such as HP, Dell, and Sony computers, including home-built PCs.

Editions of Windows

Microsoft has produced several editions of Windows, starting with Windows XP. These versions have the same core operating system, but some versions included advance features with an additional cost. There are two most common editions of Windows:

Windows Home
Windows Professional

Windows Home

Windows Home is basic edition of Windows. It offers all the fundamental functions of Windows, such as browsing the web, connecting to the Internet, playing video games, using office software, watching videos. Furthermore, it is less expensive and comes pre-installed with many new computers.

Windows Professional

Windows Professional is also known as Window Pro or win Pro. It is an enhanced edition of Windows, which is beneficial for power users and small to medium-size businesses. It contains all features of Windows Home as well as the following:

Remote Desktop: Windows Professional editions allow users to create a remote desktop connection. It provides users the option to connect with another computer remotely, including share the control of its mouse, keyboard, and view display. It is mainly accessed with the help of port 3389. Additionally, we can also use the TeamViewer or VNC application to create a remote desktop connection.
Trusted Boot: It provides security as encrypting to the boot loader and protects the computer from rootkits (Collection of software tools that allow users to enter another computer through an unauthorized way known as rootkits).
Bitlocker: It allows users to encrypt a storage drive by using AES (Advanced Encryption Standard) algorithm. This feature is present in Windows 7, and Windows Vista (Only ultimate and Enterprise versions), including Windows Server 2008.

Business laptops or computers mainly use the Bitlocker feature to protect their data on the computer. As if your computer has been stolen, it is very difficult to break the Bitlocker password. It can be unlocked by entering the correct password only. Furthermore, if you forget your Bitlocker password, it cannot be retrieved.

Windows Sandbox: A sandbox is located on a computer, network, or an online service enables users to experiment or test computer security without interrupting the system.
Hyper-V: It stands for a hypervisor, and developed by Microsoft Corporation on 26 June 2008. It is also called Windows Server Virtualization. Hyper-V is used for virtualization of x86-64 servers, running virtual machines and third party software like VirtualBox.
Group policy management: An admin can specify group policies in an organization to manage different Windows users.
It provides support for the systems that have more than 128 GB of RAM.
Furthermore, it also offers more Windows update installation options as well as flexible scheduling and postponement around 34 days.

Why is Microsoft Windows called Windows?

When Microsoft Windows was not introduced, all of the Microsoft users were used MS-DOS operating system. Microsoft gave one word to most of its products; it required a new Word that can represent its new GUI operating system. Microsoft decided to call it Windows because it has the ability to perform several tasks and run applications simultaneously.

Another reason behind calling it Windows was that you could not trademark a common name like Windows. Its official name was Microsoft Windows, the first version 1.0 of Windows was introduced in 1995.

History of Microsoft Windows

Since 1983, Microsoft is producing Windows. The founder of Microsoft 'Bill Gates' announced for Microsoft Windows on 10 November 1983 and released the first version of Windows in 1985. The following table contains history of Windows from edition 1 to 10.

Version	History
Windows 1.0	Microsoft introduced Windows with its first version 1.0. It was released on 20 November 1985, and at the beginning, it was sold for $100.00. Additionally, it was the first effort by Microsoft to produce a graphical user interface in 16-bit.
Windows 2.0	The second version, Windows 2.0, was produced by Microsoft on 9 December 1987 as well as it also introduced the Window 386 on the same day. Initially, the price was the same $100.00 for both of the Windows in the market. It came with new features such as it was able to overlap each other, and it also introduced the new way to maximize and minimize the window, instead of using 'zooming' and 'iconizing' respectively. Furthermore, it also included the control panel feature where several system settings and configuration options are available in one place. Even Microsoft Word and Excel were also used for the first time on Windows 2.
Windows 286	It was released in June 1988, and at the beginning, its price was $100.00.
Windows 3.0	It was the first Windows that needed a hard drive. It was launched by Microsoft on 22 May 1990. Its full version was sold for $149.95, and the updated version was $79.95. Additionally, the multimedia supported Windows 3 was introduced in October 1991. Windows version 3.0 gained more success, and it became a challenge for Apple's Macintosh and the Commodore Amiga GUI as it was provided pre-installed on computers by PC compatible manufacturers as well as Zenith Data Systems. It was also able to run the MS-DOS program in Windows that allowed multitasking in legacy programs as well as supported 256 colors, which made the interface more colorful and advanced.
Windows 3.1	It was launched in April 1992, when it was in development its code name was Sparta. It was the commonly used operating system for the PC graphical user interface. In the first two months after its release, more than one million copies were sold. It made the Windows usable publishing platform for the first time by introducing the TrueType fonts. Minesweeper was also used for the first time on the Windows 3.1. It was needed only 1MB of RAM to run, and it allowed users to control the MS-DOS programs with the help of a mouse for the first time. Furthermore, it was also the first operating system to be distributed on a CD-ROM. Some other generations of version 3.1 are as follows: In 1992, the Windows for Workgroups 3.1 was launched. Microsoft introduced Windows NT 3.1 on 27 July 1993. An updated version of Windows 3.1, Windows 3.11, was introduced on 31 December 1993. In February 1994, the Windows for Workgroups 3.11 was launched. On 21 September 1994, the Windows NT 5 was introduced. The next version Windows NT 3.51, was introduced on 30 May 1995.
Windows 95	As the name specifies, Windows 95 was launched on 24 August 1995, and within four days of its release, more than one million copies were sold. It introduced the Start button and Start menu features for the first time, including important features such as a 32-bit environment, multitasking, and taskbar. Furthermore, MS-DOS still played a vital role in Windows 95, with the help of some programs and elements. Internet Explorer was also used on the Windows 95 for the first time, but it could not be installed by default, it needed the Windows 95 plus pack for it. Later, Windows 95 improved and included the IE browser by default.
Windows 95 Service Pack	It was introduced on 24 February 1996.
Windows NT 4.0	On 29 July 1996, Windows NT 4.0 was launched.
Windows CE	The first version 0 of Windows CE was introduced in November 1996. The Second version 0 of Windows CE was launched in November 1997. The next version 1 of Windows CE was released in July 1998. The third version, 3.0 of Windows CE, was introduced in 1999.
Windows 98	It was developed on Windows 95, and introduced in June 1998. It was released, including Internet Explorer 4, Windows Address Book, Outlook Express, Microsoft Chat, and NetShow Player. The second version of Windows 98 was introduced on 5 May 1999, in this version the NetShow Player was replaced by Windows Media Player 6.2. It was also brought with the address bar and back/forward navigation buttons in Windows Explorer, and more other features. Windows 98 came with the new feature Windows Driver model for computer components and accessories, which offered support to all future editions of Windows. Furthermore, it was improved USB support including USB mice and USB hubs.
Windows 2000	On 17 February 2000, it was launched.
Windows ME	It was invented in September 2000, and it was the last operating system, which was based on MS-DOS and in the Windows 9x line. According to the enterprise market, it was considered consumer-aimed Windows with the Windows 2000. It was also provided some useful features for consumers as well as more automated system recovery tools. Additionally, an Internet Explorer, Windows Movie Maker, and Windows Media Player 7 were used on Windows ME for the first time.
Windows 2000	It was introduced on 17 February 2000. Basically, it was based on Microsoft business-oriented system Windows NT, and later it provided the base for the Windows XP. Furthermore, the automatic updating feature made their appearance for the first time on Windows 2000, and it was the first operating system to support hibernation.
Windows XP	Windows XP was considered the best edition of Windows; it was introduced on 25 October 2001. It followed Windows ME and provided consumer-friendly elements. The 64-bit version of Windows XP was introduced on 28 March 2003. Furthermore, Its Professional x64 version was introduced on 24 April 2005. The start button and taskbar were replaced by including the green Start button, blue task bar, and vista wallpaper, as well as several shadows and more visual effects. It also brought some important features, such as ClearType, which helps to read content on LCD screens, autoplay from CDs and other media, different automated update, and recovery tools. Additionally, It was used for the longest time, and even when it was discontinued, it was used at an estimated 430 m PC.
Windows Vista	It was introduced by Microsoft In January 2007. It was brought the better look and feel user interface and included transparent elements, security, and search. When it was in the development phase, its code name was "Longhorn." Windows Media Player 11 and Internet Explorer 7 were made their appearance for the first time on Windows Vista, included Windows Defender, an anti-spyware program. It was also provided some useful features such as Windows DVD Maker, speech recognition, and Photo Gallery. Furthermore, it was the first operating system to be distributed on DVD.
Windows Server 2008	On 27 February 2008, Microsoft introduced Windows Server 2008.
Windows 7	It was introduced on 22 October 2009 to overcome all problems that were faced by Windows Vista. It was released with user-friendly features and less dialogue box overload. It was more stable, faster, and easy to use as compared to release other previous versions. Additionally, the handwriting recognition feature was used for the first time on Windows 7. As IE was the default browser in Microsoft Windows, the antitrust investigations used Microsoft in Europe for making it a default browser. Consequently, it had to provide the users the option to choose and install the browser on the first boot.
Windows Server 2012	On 4 September 2012, Microsoft was released Windows Server 2012.
Windows 8	It was introduced by Microsoft on 26 October 2012. It was released with new features, such as a fast operating system, support for the USB 3.0 devices, and Web store. The Web store is a place where you can download different types of Windows applications; its full-screen mode was run for the first time on Windows 8.
Windows 8.1	It was launched by Microsoft on 17 October 2013. It was re-launched the Start button, which was able to display the Start screen from the desktop view of Windows 8.1. Furthermore, it provided a way to select boot directly into the desktop.
Windows 10	On 29 July 2015, Microsoft introduced Windows 10. It was released with some new features such as switching between a keyboard and mouse mode and a tablet mode, which was beneficial for the users who use computers like surface Pro 3 with a detachable keyboard. It was designed for all Windows platforms across several devices, as well as Windows tablets and Phones, including common applications.

Features of Windows

Microsoft Windows includes a lot of features to help users. Some of its excellent features are as follows:

Control Panel: Windows provides a Control Panel feature that includes many tools to configure and manage the resources on their computer. For example, users can change settings for audio, video, printers, mouse, keyboard, network connections, date and time, power saving options, user accounts, installed applications, etc.

Cortana: Windows 10 introduced a feature named Cortana, which is able to accept voice commands. It can perform various tasks such as it can answers your questions, search data on your computer, online purchases, set reminders, and appointments, etc. Furthermore, it acts like other voice-activated services such as Google Assistant, Alexa, or Siri, including one more benefit of searching the information on your computer. To open the Cortana in Windows 10, press Window key + S.

File Explorer: It is also known as Windows Explorer, which displays your files and folders on the computer. It allows users to browse the data on the hard drive, SSD and other inserted removable disks like pen drives and CDs, and you can manage the content according to the requirements such as delete, rename, search, and transfer the data.
Internet browser: As the internet browser is very important to search for anything, view pages, online shopping, play games, watch videos, etc. Windows come with a pre-installed internet browser. in Windows 10, the Edge internet browser is the default browser. Furthermore, Internet Explorer was the default browser in Microsoft Windows from the Windows edition 95 to 8.1 version.
Microsoft Paint: Since November 1985, Microsoft Windows comes with pre-installed Microsoft Paint. It is a simple software to create, view, and edit an image. It offers several tools to draw an image, crop, resize, and save an image with a different file extension.

Taskbar: Windows comes with a taskbar that displays currently opened programs, it also allows users to access any specific programs. Additionally, it includes the notification area on the right side that shows date and time, battery, network, volume, and other background running applications.

Start menu: Microsoft Windows contains a start menu to the left side of the taskbar. It displays programs and utilities that are installed on the computer. It can be simply opened by clicking on the Start menu button or pressing the start key on the keyboard.

Task Manager: Windows includes the task manager feature that provides detail of the running applications or programs on the computer. You can also check how much of the system resources, such as RAM, CPU, disk I/O, are being used by each of the applications.

Disk Cleanup: It is used to free up disk space with the help of deleting temporary or unnecessary files. It also helps to enhance the performance of the computer, and boost storage space to download the programs and documents. To open Disk Cleanup, follow the below steps:

Open the File Explorer by pressing Window + E.
Then, right-click on any disk drive and select Properties option from the drop-down list.
Now, click on the Disk Cleanup.

Difference between Linux and Windows OS

Below is a table to describe the major factors about Linux and Windows operating systems:

Topic	Windows	Linux
Command Line	Windows allows users to use the command line, but not as a Linux command line. To open the command line, click on the Run dialog box and type CMD in the run search bar and press Enter key.	Although the Linux command-line offers more features for administration and daily tasks, it does not offer much to end-users.
Reliability	Windows has improved its reliability in the past few years, but still it is less reliable as compared to Linux.	Linux is more reliable and secure then Windows OS. It mainly focuses on system security, process management, and up-time.
Usability	Windows is easier to use as it provides a simple user interface. But its installation process can take more time.	Although Linux has the ability to perform complex tasks easier, its installation process is complicated.
Security	Microsoft has enhanced the security features in Windows over recent years. As it has a huge user base, mostly for new computer users, it can be easily targeted for malicious coders. Furthermore, among all of the operating systems, Microsoft Windows can be part of developing malware and viruses.	Linux is a more secure operating system as compared to Microsoft Windows. Even attackers found difficulty in breaking the security with the help of Linux.
Support	It provides users the online and integrated help systems, as well as a large number of informative books, are available to provide help for people at all skill levels.	A wide number of books are available to offer help about Linux, including online support.
Updates	Regular Windows update makes users frustrated by alerting the Windows update for inconvenient times. Additionally, it takes more time to get an update.	Linux provides users full control over updates. They can update it accordingly, and it takes less time to get an update as well as without any reboot the system.
Licensing	Microsoft Windows with license does not allow to modify the software (don't have access to the source code). It can be installed only on the systems with a Windows license key.	Linux operating system with a license offers users the benefit to re-use the source code on any number of systems. It is also allowed the users to modify the software and sell its modified version.

Hardware

2021-07-08T11:50:00.003+05:30

Hardware

Hardware, which is abbreviated as HW, refers to all physical components of a computer system, including the devices connected to it. You cannot create a computer or use software without using hardware. The screen on which you are reading this information is also a hardware.

What is a hardware upgrade?

A hardware upgrade refers to a new hardware, or a replacement for the old one, or additional hardware developed to improve the performance of the existing hardware. A common example of a hardware upgrade is a RAM upgrade that increases the computer's total memory, and video card upgrade, where the old video card is removed and replaced with the new one.

Some of the commonly used hardware in your computer are described below:

1) Motherboard:

The motherboard is generally a thin circuit board that holds together almost all parts of a computer except input and output devices. All crucial hardware like CPU, memory, hard drive, and ports for input and output devices are located on the motherboard. It is the biggest circuit board in a computer chassis.

It allocates power to all hardware located on it and enables them to communicate with each other. It is meant to hold the computer's microprocessor chip and let other components connect to it. Each component that runs the computer or improves its performance is a part of the motherboard or connected to it through a slot or port.

There can be different types of motherboards based on the type and size of the computers. So, a specific motherboard can work only with specific types of processors and memory.

Components of a Motherboard:

CPU Slot: It is provided to install the CPU. It is a link between a microprocessor and a motherboard. It facilitates the use of CPU and prevents the damage when it is installed or removed. Furthermore, it is provided with a lock to prevent CPU movement and a heat sink to dissipate the extra heat.

RAM Slot: It is a memory slot or socket provided in the motherboard to insert or install the RAM (Random Access Memory). There can be two or more memory slots in a computer.

Expansion Slot: It is also called the bus slot or expansion port. It is a connection or port on the motherboard, which provides an installation point to connect a hardware expansion card, for example, you can purchase a video expansion card and install it into the expansion slot and then can install a new video card in the computer. Some of the common expansion slots in a computer are AGP, AMR, CNR, PCI, etc.

Capacitor: It is made of two conductive plates, and a thin insulator sandwiched between them. These parts are wrapped in a plastic container.

Inductor (Coil): It is an electromagnetic coil made of a conducting wire wrapped around an iron core. It acts as an inductor or electromagnet to store magnetic energy.

Northbridge: It is an integrated circuit that allows communications between the CPU interface, AGP, and memory. Furthermore, it also allows the southbridge chip to communicate with the RAM, CPU, and graphics controller.

USB Port: It allows you to connect hardware devices like mouse, keyboard to your computer.

PCI Slot: It stands for Peripheral Component Interconnect slot. It allows you to connect the PCI devices like modems, network hardware, sound, and video cards.

AGP Slot: It stands for Accelerated Graphics Port. It provides the slot to connect graphics cards.

Heat Sink: It absorbs and disperses the heat generated in the computer processor.

Power Connector: It is designed to supply power to the motherboard.

CMOS battery: It stands for complementary metal-oxide-semiconductor. It is a memory that stores the BIOS settings such as time, date, and hardware settings.

2) Monitor:

A monitor is the display unit of a computer on which the processed data, such as text, images, etc., is displayed. It comprises a screen circuity and the case which encloses this circuity. The monitor is also known as a visual display unit (VDU).

Types of Monitors:

CRT Monitor: It has cathode ray tubes which produce images in the form of video signals. Its main components are electron gun assembly, deflection plate assembly, glass envelope, fluorescent screen, and base.
LCD Monitor: It is a flat panel screen. It uses liquid crystal display technology to produce images on the screen. Advanced LEDs have thin-film transistors with capacitors and use active-matrix technology, which allows pixels to retain their charge.
LED Monitor: It is an advanced version of an LCD monitor. Unlike an LCD monitor, which uses cold cathode fluorescent light to backlight the display, it has LED panels, each of which has lots of LEDs to display the backlight.
Plasma Monitor: It uses plasma display technology that allows it to produce high resolutions of up to 1920 X 1080, wide viewing angle, a high refresh rate, outstanding contrast ration, and more.

3) Keyboard:

It is the most important input device of a computer. It is designed to allow you input text, characters, and other commands into a computer, desktop, tablet, etc. It comes with different sets of keys to enter numbers, characters, and perform various other functions like copy, paste, delete, enter, etc.

Types of Keyboards:

QWERTY Keyboards
AZERTY Keyboards
DVORAK Keyboards

4) Mouse:

It is a small handheld device designed to control or move the pointer (computer screen's cursor) in a GUI (graphical user interface). It allows you to point to or select objects on a computer's display screen. It is generally placed on a flat surface as we need to move it smoothly to control the pointer. Types of Mouse: Trackball mouse, Mechanical Mouse, Optical Mouse, Wireless Mouse, etc.

Main functions of a mouse:

Move the cursor: It is the main function of the mouse; to move the cursor on the screen.
Open or execute a program: It allows you to open a folder or document and execute a program. You are required to take the cursor on the folder and double click it to open it.
Select: It allows you to select text, file, or any other object.
Hovering: Hovering is an act of moving the mouse cursor over a clickable object. During hovering over an object, it displays information about the object without pressing any button of the mouse.
Scroll: It allows you to scroll up or down while viewing a long webpage or document.

Parts of a mouse:

Two buttons: A mouse is provided with two buttons for right click and left click.
Scroll Wheel: A wheel located between the right and left buttons, which is used to scroll up and down and Zoom in and Zoom out in some applications like AutoCAD.
Battery: A battery is required in a wireless mouse.
Motion Detection Assembly: A mouse can have a trackball or an optical sensor to provide signals to the computer about the motion and location of the mouse.

Central Processing Unit

2021-07-08T10:57:00.002+05:30

Central Processing Unit (CPU)

A Central Processing Unit is also called a processor, central processor, or microprocessor. It carries out all the important functions of a computer. It receives instructions from both the hardware and active software and produces output accordingly. It stores all important programs like operating systems and application software. CPU also helps Input and output devices to communicate with each other. Owing to these features of CPU, it is often referred to as the brain of the computer.

CPU is installed or inserted into a CPU socket located on the motherboard. Furthermore, it is provided with a heat sink to absorb and dissipate heat to keep the CPU cool and functioning smoothly.

Generally, a CPU has three components:

ALU (Arithmetic Logic Unit)
Control Unit
Memory or Storage Unit

Control Unit: It is the circuitry in the control unit, which makes use of electrical signals to instruct the computer system for executing already stored instructions. It takes instructions from memory and then decodes and executes these instructions. So, it controls and coordinates the functioning of all parts of the computer. The Control Unit's main task is to maintain and regulate the flow of information across the processor. It does not take part in processing and storing data.

ALU: It is the arithmetic logic unit, which performs arithmetic and logical functions. Arithmetic functions include addition, subtraction, multiplication division, and comparisons. Logical functions mainly include selecting, comparing, and merging the data. A CPU may contain more than one ALU. Furthermore, ALUs can be used for maintaining timers that help run the computer.

Memory or Storage Unit/ Registers: It is called Random access memory (RAM). It temporarily stores data, programs, and intermediate and final results of processing. So, it acts as a temporary storage area that holds the data temporarily, which is used to run the computer.

What is CPU Clock Speed?

The clock speed of a CPU or a processor refers to the number of instructions it can process in a second. It is measured in gigahertz. For example, a CPU with a clock speed of 4.0 GHz means it can process 4 billion instructions in a second.

Types of CPU:

CPUs are mostly manufactured by Intel and AMD, each of which manufactures its own types of CPUs. In modern times, there are lots of CPU types in the market. Some of the basic types of CPUs are described below:

Single Core CPU: Single Core is the oldest type of computer CPU, which was used in the 1970s. It has only one core to process different operations. It can start only one operation at a time; the CPU switches back and forth between different sets of data streams when more than one program runs. So, it is not suitable for multitasking as the performance will be reduced if more than one application runs. The performance of these CPUs is mainly dependent on the clock speed. It is still used in various devices, such as smartphones.

Dual Core CPU: As the name suggests, Dual Core CPU contains two cores in a single Integrated Circuit (IC). Although each core has its own controller and cache, they are linked together to work as a single unit and thus can perform faster than the single-core processors and can handle multitasking more efficiently than Single Core processors.

Quad Core CPU: This type of CPU comes with two dual-core processors in one integrated circuit (IC) or chip. So, a quad-core processor is a chip that contains four independent units called cores. These cores read and execute instructions of CPU. The cores can run multiple instructions simultaneously, thereby increases the overall speed for programs that are compatible with parallel processing.

Quad Core CPU uses a technology that allows four independent processing units (cores) to run in parallel on a single chip. Thus by integrating multiple cores in a single CPU, higher performance can be generated without boosting the clock speed. However, the performance increases only when the computer's software supports multiprocessing. The software which supports multiprocessing divides the processing load between multiple processors instead of using one processor at a time.

History of CPU:

Some of the important events in the development of CPU since its invention till date are as follows:

In 1823, Baron Jons Jackob Berzelius discovered silicon that is the main component of CPU till date.
In 1903, Nikola Tesla got gates or switches patented, which are electrical logic circuits.
In December 1947, John Bardeen, William Shockley, and Walter Brattain invented the first transistor at the Bell Laboratories and got it patented in 1948.
In 1958, the first working integrated circuit was developed by Robert Noyce and Jack Kilby.
In 1960, IBM established the first mass-production facility for transistors in New York.
In 1968, Robert Noyce and Gordon Moore founded Intel Corporation.
AMD (Advanced Micro Devices) was founded in May 1969.
In 1971, Intel introduced the first microprocessor, the Intel 4004, with the help of Ted Hoff.
In 1972, Intel introduced the 8008 processor; in 1976, Intel 8086 was introduced, and in June 1979, Intel 8088 was released.
In 1979, a 16/32-bit processor, the Motorola 68000, was released. Later, it was used as a processor for the Apple Macintosh and Amiga computers.
In 1987, Sun introduced the SPARC processor.
In March 1991, AMD introduced the AM386 microprocessor family.
In March 1993, Intel released the Pentium processor. In 1995, Cyrix introduced the Cx5x86 processor to give competition to Intel Pentium processors.
In January 1999, Intel introduced the Celeron 366 MHz and 400 MHz processors.
In April 2005, AMD introduced its first dual-core processor.
In 2006, Intel introduced the Core 2 Duo processor.
In 2007, Intel introduced different types of Core 2 Quad processors.
In April 2008, Intel introduced the first series of Intel Atom processors, the Z5xx series. They were single-core processors with a 200 MHz GPU.
In September 2009, Intel released the first Core i5 desktop processor with four cores.
In January 2010, Intel released many processors such as Core 2 Quad processor Q9500, first Core i3 and i5 mobile processors, first Core i3 and i5 desktop processors. In the same year in July, it released the first Core i7 desktop processor with six cores.
In June 2017, Intel introduced the first Core i9 desktop processor.
In April 2018, Intel released the first Core i9 mobile processor.

Output Devices

2021-07-08T10:53:00.001+05:30

Output Devices

The output device displays the result of the processing of raw data that is entered in the computer through an input device. There are a number of output devices that display output in different ways such as text, images, hard copies, and audio or video.

Some of the popular output devices are:

Monitor
- CRT Monitor
- LCD Monitor
- LED Monitor
- Plasma Monitor
Printer
- Impact Printers
  1. Character Printers
    1. Dot Matrix printers
    2. Daisy Wheel printers
  2. Line printers
    1. Drum printers
    2. Chain printers
- Non-impact printers
  1. Laser printers
  2. Inkjet printers
Projector

1) Monitor

The monitor is the display unit or screen of the computer. It is the main output device that displays the processed data or information as text, images, audio or video.

The types of monitors are given below.

i) CRT Monitor

CRT monitors are based on the cathode ray tubes. They are like vacuum tubes which produce images in the form of video signals. Cathode rays tube produces a beam of electrons through electron guns that strike on the inner phosphorescent surface of the screen to produce images on the screen. The monitor contains millions of phosphorus dots of red, green and blue color. These dots start to glow when struck by electron beams and this phenomenon is called cathodoluminescence.

The main components of a CRT monitor include the electron gun assembly, deflection plate assembly, fluorescent screen, glass envelope, and base.The front (outer surface) of the screen onto which images are produced is called the face plate. It is made up of fiber optics.

There are three electron beams that strike the screen: red, green, and blue. So, the colors which you see on the screen are the blends of red, blue and green lights.The magnetic field guides the beams of electrons. Although LCDs have replaced the CRT monitors, the CRT monitors are still used by graphics professionals because of their color quality.

ii) LCD Monitor

The LCD monitor is a flat panel screen that is compact and light-weight as compared to CRT monitors. It is based on liquid crystal display technology which is used in the screens of laptops, tablets, smart phones, etc. An LCD screen comprises two layers of polarized glass with a liquid crystal solution between them. When the light passes through the first layer, an electric current aligns the liquids crystals. The aligned liquid crystals allow a varying level of light to pass through the second layer to create images on the screen.

The LCD screen has a matrix of pixels that display the image on the screen.Old LCDs had passive-matrix screens in which individual pixels are controlled by sending a charge. A few electrical charges could be sent each second that made screens appear blurry when the images moved quickly on the screen.

Modern LCDs use active-matrix technology and contain thin film transistors (TFTs) with capacitors. This technology allows pixels to retain their charge. So, they don?t make screen blurry when images move fast on the screen as well as are more efficient than passive-matrix displays.

iii) LED monitor

The LED monitor is an improved version of an LCD monitor. It also has a flat panel display and uses liquid crystal display technology like the LCD monitors. The difference between them lies in the source of light to backlight the display. The LED monitor has many LED panels, and each panel has several LEDsto backlight the display, whereas the LCD monitors use cold cathode fluorescent light to backlight the display.Modern electronic devices such as mobile phones, LED TVs, laptop and computer screens, etc., use a LED display as it not only produces more brilliance and greater light intensity but also consumes less power.

iv) Plasma Monitor

The plasma monitor is also a flat panel display that is based on plasma display technology. It has small tiny cells between two glass panels. These cells contain mixtures of noble gases and a small amount of mercury. When voltage is applied, the gas in the cells turns into a plasma and emits ultraviolet light that creates images on the screen, i.e., the screen is illuminated by a tiny bit of plasma, a charged gas. Plasma displays are brighter than liquid crystal displays (LCD) and also offer a wide viewing angle than an LCD.

Plasma monitors provide high resolutions of up to 1920 X 1080, excellent contrast ratios, wide viewing angle, a high refresh rate and more. Thus, they offer a unique viewing experience while watching action movies, sports games, and more.

2) Printer

A printer produces hard copies of the processed data. It enables the user, to print images, text or any other information onto the paper.

Based on the printing mechanism, the printers are of two types: Impact Printers and Non-impact Printers.

Impact Printers: They are of two types:
1. Character Printers
  1. Dot Matrix printers
  2. Daisy Wheel printers
2. Line printers
  1. Drum printers
  2. Chain printers
Non-impact printers: They are of two types:
1. Laser printers
2. Inkjet printers

Impact Printer

The impact printer uses a hammer or print head to print the character or images onto the paper. The hammer or print head strikes or presses an ink ribbon against the paper to print characters and images.

Impact printers are further divided into two types.

Character Printers
Line printers

A) Character Printers

Character printer prints a single character at a time or with a single stroke of the print head or hammer. It does not print one line at a time. Dot Matrix printer and Daisy Wheel printer are character printers. Today, these printers are not in much use due to their low speed and because only the text can be printed. The character printers are of two types, which are as follows:

i) Dot Matrix Printer

Dot Matrix Printer is an impact printer. The characters and images printed by it are the patterns of dots. These patterns are produced by striking the ink soaked ribbon against the paper with a print head. The print head contains pins that produce a pattern of dots on the paper to form the individual characters. The print head of a 24 pin dot matrix contains more pins than a 9 pin dot matrix printer, so it produces more dots which results in better printing of characters. To produce color output, the black ribbon can be changed with color stripes. The speed of Dot Matrix printers is around 200-500 characters per second.

ii) Daisy Wheel Printer

Daisy Wheel Printer was invented by David S. Lee at Diablo Data Systems.It consists of a wheel or disk that has spokes or extensions and looks like a daisy, so it is named Daisy Wheel printer. At the end of extensions, molded metal characters are mounted. To print a character the printer rotates the wheel, and when the desired character is on the print location the hammer hits disk and the extension hits the ink ribbon against the paper to create the impression. It cannot be used to print graphics and is often noisy and slow, i.e., the speed is very low around 25-50 characters per second. Due to these drawbacks,these printers have become obsolete.

B) Line Printers:

Line printer, which is also as a bar printer, prints one line at a time. It is a high-speed impact printer as it can print 500 to 3000 lines per minute. Drum printer and chain printer are examples of line printers.

i) Drum Printer:

Drum printer is a line printer that is made of a rotating drum to print characters. The drum has circular bands of characters on its surface. It has a separate hammer for each band of characters. When you print, the drum rotates, and when the desired character comes under the hammer, the hammer strikes the ink ribbon against the paper to print characters. The drum rotates at a very high speed and characters are printed by activating the appropriate hammers. Although all the characters are not printed at a time, they are printed at a very high speed. Furthermore, it can print only a predefined style as it has a specific set of characters. These printers are known to be very noisy due to the use of hammering techniques.

ii) Chain Printer:

Chain printer is a line printer that uses a rotating chain to print characters. The characters are embossed on the surface of the chain. The chain rotates horizontally around a set of hammers, for each print location one hammer is provided, i.e., the total number of hammers is equal to the total number of print positions.

The chain rotates at a very high speed and when the desired character comes at the print location, the corresponding hammer strikes the page against the ribbon and character on the chain.They can type 500 to 3000 lines per minute. They are also noisy due to the hammering action.

Non-Impact Printer:

Non-impact printers don't print characters or images by striking a print head or hammer on the ink ribbon placed against the paper. They print characters and images without direct physical contact between the paper and the printing machinery. These printers can print a complete page at a time, so they are also known as page printers. The common types of non-impact printers are Laser printer and Inkjet printer:

i) Laser Printer:

A laser printer is a non-impact printer that uses a laser beam to print the characters. The laser beam hits the drum, which is a photoreceptor and draws the image on the drum by altering electrical charges on the drum. The drum then rolls in toner, and the charged image on the drum picks the toner. The toner is then printed on the paper using heat and pressure. Once the document is printed, the drum loses the electric charge,and the remaining toner is collected. The laser printers use powdered toner for printing instead of liquid ink and produce quality print objects with a resolution of 600 dots per inch (dpi) or more.

ii) Inkjet Printer:

The inkjet printer is a non-impact printer that prints images and characters by spraying fine,ionized drops of ink. The print head has tiny nozzles to spray the ink. The printer head moves back and forth and sprays ionized drops of ink on the paper, which is fed through the printer. These drops pass through an electric field that guides the ink onto the paper to print correct images and characters.

An inkjet printer has cartridges that contain ink. Modern inkjet printers are color printers that have four cartridges containing different colors: Cyan, Magenta, Yellow, and Black. It is capable of printing high-quality images with different colors. It can produce print objects with a resolution of at least 300 dots per inch (dpi).

3) Projector

A projector is an output device that enables the user to project the output onto a large surface such as a big screen or wall. It can be connected to a computer and similar devices to project their output onto a screen. It uses light and lenses to produce magnified texts, images, and videos. So, it is an ideal output device to give presentations or to teach a large number of people.

Modern projects (digital projectors) come with multiple input sources such as HDMI ports for newer equipment and VGA ports that support older devices. Some projectors are designed to support Wi-Fi and Bluetooth as well. They can be fixed onto the ceiling, placed on a stand, and more and are frequently used for classroom teaching, giving presentations, home cinemas, etc.

A digital projector can be of two types:

Liquid Crystal Display (LCD) digital projector: This type of digital projectors are very popular as they are lightweight and provide crisp output. An LCD projector uses transmissive technology to produce output. It allows the light source, which is a standard lamp, to pass through the three colored liquid crystal light panels. Some colors pass through the panels and some are blocked by the panels and thus images are on the screen.

Digital Light Processing (DLP) digital projector: It has a set of tiny mirrors, a separate mirror for each pixel of the image and thus provide high-quality images. These projectors are mostly used in theatres as they fulfill the requirement of high-quality video output.

What is Universal Serial Bus(USB)

2021-07-08T09:37:00.000+05:30

USB: Universal Serial Bus

Universal Serial Bus is an industry standard used to define the cables, connectors and communication protocols used in a bus for connection, communication and power supply between computers and electronic devices.

USB was designed to support data transfer and supply electric power between peripheral devices such as mouse, keyboard, printer, portable media players, disk drive etc.

History

USB was developed in 1994 by a group of seven companies. Compaq, DEC, IBM, Microsoft, Intel, NEC, and Nortel. It was developed to make easy to connect external devices to PC. An USB device can be used across multiple platforms like Windows, Mac, and Linux.

How to connect USB device with Computer

It is very simple to connect USB device with computers. Just insert the USB device in the computer?s USB port and it will detect the device and start working. It does not ask for rebooting your computer when inserted. Universal Serial Bus Drive is the most commonly used USB device.

There are three basic sizes of USB connectors:

Standard size
Mini size
Micro size

Input Devices

2021-07-08T09:34:00.151+05:30

Input Devices

Input device enables the user to send data, information, or control signals to a computer. The Central Processing Unit (CPU) of a computer receives the input and processes it to produce the output.

Some of the popular input devices are:

1) Keyboard

The keyboard is a basic input device that is used to enter data into a computer or any other electronic device by pressing keys. It has different sets of keys for letters, numbers, characters, and functions. Keyboards are connected to a computer through USB or a Bluetooth device for wireless communication.

Types of keyboards: There can be different types of keyboards based on the region and language used. Some of the common types of keyboards are as follows:

I) QWERTY Keyboard:

It is the most commonly used keyboard with computers in modern times. It is named after the first six letters of the top row of buttons and is even popular in countries that do not use Latin-based alphabet. It is so popular that some people think that it is the only type of keyboard to use with computers as an input device.

II) AZERTY Keyboard:

It is considered the standard French keyboard. It is developed in France as an alternative layout to the QWERTY layout and is mainly used in France and other European countries. Some countries have manufactured their own versions of AZERTY.

Its name is derived from the first six letters that appear on the top left row of the keyboard. The Q and W keys in AZERTY keyboard are interchanged with A and Z keys in QWERTY keyboard. Furthermore, in AZERTY keyboard M key is located to the left of the L key.

AZERTY keyboard differs from QWERTY keyboard not only in the placement of letters but also in many other ways, e.g., it gives emphasis on accents, which is required for writing European languages like French.

III) DVORAK Keyboard:

This type of keyboard layout was developed to increase the typing speed by reducing the finger movement while typing. The most frequently used letters are kept in a home row to improve typing.

2) Mouse

The mouse is a hand-held input device which is used to move cursor or pointer across the screen. It is designed to be used on a flat surface and generally has left and right button and a scroll wheel between them. Laptop computers come with a touchpad that works as a mouse. It lets you control the movement of cursor or pointer by moving your finger over the touchpad. Some mouse comes with integrated features such as extra buttons to perform different buttons.

The mouse was invented by Douglas C. Engelbart in 1963. Early mouse had a roller ball integrated as a movement sensor underneath the device. Modern mouse devices come with optical technology that controls cursor movements by a visible or invisible light beam. A mouse is connected to a computer through different ports depending on the type of computer and type of a mouse.

Common types of the mouse:

I) Trackball Mouse:

It is a stationary input device that has ball mechanism to move the pointer or cursor on the screen. The ball is half inserted in the device and can be easily rolled with finger, thumb or the palm to move the pointer on the screen. The device has sensor to detect the rotation of ball. It remains stationary; you don't need to move it on the operating surface. So, it is an ideal device if you have limited desk space as you don't need to move it like a mouse.

II) Mechanical Mouse:

It has a system of a ball and several rollers to track its movement. It is a corded type of mouse. A mechanical mouse can be used for high performance. The drawback is that they tend to get dust into the mechanics and thus require regular cleaning.

III) Optical Mouse:

An optical mouse uses optical electronics to track its movement. It is more reliable than a mechanical mouse and also requires less maintenance. However, its performance is affected by the surface on which it is operated. Plain non-glossy mouse mat should be used for best results. The rough surface may cause problems for the optical recognition system, and the glossy surface may reflect the light wrongly and thus may cause tracking issues.

IV) Cordless or Wireless Mouse:

As the name suggests, this type of mouse lacks cable and uses wireless technology such as IrDA (infrared) or radio (Bluetooth or Wi-Fi) to control the movement of the cursor. It is used to improve the experience of using a mouse. It uses batteries for its power supply.

3) Scanner

The scanner uses the pictures and pages of text as input. It scans the picture or a document. The scanned picture or document then converted into a digital format or file and is displayed on the screen as an output. It uses optical character recognition techniques to convert images into digital ones. Some of the common types of scanners are as follows:

Types of Scanner:

I) Flatbed Scanner:

It has a glass pane and a moving optical CIS or CCD array. The light illuminates the pane, and then the image is placed on the glass pane. The light moves across the glass pane and scans the document and thus produces its digital copy. You will need a transparency adapter while scanning transparent slides.

II) Handheld Scanner:

It is a small manual scanning device which is held by hand and is rolled over a flat image that is to be scanned. The drawback in using this device is that the hand should be steady while scanning; otherwise, it may distort the image. One of the commonly used handheld scanners is the barcode scanner which you would have seen in shopping stores.

III) Sheetfed Scanner:

In this scanner, the document is inserted into the slot provided in the scanner. The main components of this scanner include the sheet-feeder, scanning module, and calibration sheet. The light does not move in this scanner. Instead, the document moves through the scanner. It is suitable for scanning single page documents, not for thick objects like books, magazines, etc.

IV) Drum Scanner:

Drum scanner has a photomultiplier tube (PMT) to scan images. It does not have a charge-coupled device like a flatbed scanner. The photomultiplier tube is extremely sensitive to light. The image is placed on a glass tube, and the light moves across the image, which produces a reflection of the image which is captured by the PMT and processed. These scanners have high resolution and are suitable for detailed scans.

V) Photo Scanner:

It is designed to scan photographs. It has high resolution and color depth, which are required for scanning photographs. Some photo scanners come with in-built software for cleaning and restoring old photographs.

4) Joystick

A joystick is also a pointing input device like a mouse. It is made up of a stick with a spherical base. The base is fitted in a socket that allows free movement of the stick. The movement of stick controls the cursor or pointer on the screen.

The frist joystick was invented by C. B. Mirick at the U.S. Naval Research Laboratory. A joystick can be of different types such as displacement joysticks, finger-operated joysticks, hand operated, isometric joystick, and more. In joystick, the cursor keeps moving in the direction of the joystick unless it is upright, whereas, in mouse, the cursor moves only when the mouse moves.

5) Light Pen

A light pen is a computer input device that looks like a pen. The tip of the light pen contains a light-sensitive detector that enables the user to point to or select objects on the display screen. Its light sensitive tip detects the object location and sends the corresponding signals to the CPU. It is not compatible with LCD screens, so it is not in use today. It also helps you draw on the screen if needed. The first light pen was invented around 1955 as a part of the Whirlwind project at the Massachusetts Institute of Technology (MIT).

6) Digitizer

Digitizer is a computer input device that has a flat surface and usually comes with a stylus. It enables the user to draw images and graphics using the stylus as we draw on paper with a pencil. The images or graphics drawn on the digitizer appear on the computer monitor or display screen. The software converts the touch inputs into lines and can also convert handwritten text to typewritten words.

It can be used to capture handwritten signatures and data or images from taped papers. Furthermore, it is also used to receive information in the form of drawings and send output to a CAD (Computer-aided design) application and software like AutoCAD. Thus, it allows you to convert hand-drawn images into a format suitable for computer processing.

7) Microphone

The microphone is a computer input device that is used to input the sound. It receives the sound vibrations and converts them into audio signals or sends to a recording medium. The audio signals are converted into digital data and stored in the computer. The microphone also enables the user to telecommunicate with others. It is also used to add sound to presentations and with webcams for video conferencing. A microphone can capture audio waves in different ways; accordingly the three most common types are described below:

I) Dynamic:

It is the most commonly used microphone with a simple design. It has a magnet which is wrapped by a metal coil and a thin sheet on the front end of the magnet. The sheet transfers vibrations from sound waves to the coil and from coil to electric wires which transmit the sound like an electrical signal.

II) Condenser:

It is designed for audio recording and has a very sensitive and flat frequency response. It has a front plate called diaphragm and a back plate parallel to the front plate. When sound hits the diaphragm, it vibrates the diaphragm and alters the distance between the two plates. The changes in distance are transmitted as electric signals.

III) Ribbon:

It is known for its reliability. It has a thin ribbon made of aluminum, duraluminum, or nanofilm suspended in a magnetic field. The sound waves cause vibrations in the ribbon, which generate a voltage proportional to the velocity of the vibration. The voltage is transmitted as an electrical signal. Early ribbon microphones had a transformer to increase the output voltage, but modern ribbon microphones come with advanced magnets to produce a strong signal.

8) Magnetic Ink Character Recognition (MICR)

MICR computer input device is designed to read the text printed with magnetic ink. MICR is a character recognition technology that makes use of special magnetized ink which is sensitive to magnetic fields. It is widely used in banks to process the cheques and other organizations where security is a major concern. It can process three hundred cheques in a minute with hundred-percent accuracy. The details on the bottom of the cheque (MICR No.) are written with magnetic ink. A laser printer with MICR toner can be used to print the magnetic ink.

The device reads the details and sends to a computer for processing. A document printed in magnetic ink is required to pass through a machine which magnetizes the ink, and the magnetic information is then translated into characters.

9) Optical Character Reader (OCR)

OCR computer input device is designed to convert the scanned images of handwritten, typed or printed text into digital text. It is widely used in offices and libraries to convert documents and books into electronic files.

It processes and copies the physical form of a document using a scanner. After copying the documents, the OCR software converts the documents into a two-color (black and white), version called bitmap. Then it is analyzed for light and dark areas, where the dark areas are selected as characters, and the light area is identified as background. It is widely used to convert hard copy legal or historic documents into PDFs. The converted documents can be edited if required like we edit documents created in ms word.

10) Digital camera:

It is a digital device as it captures images and records videos digitally and then stores them on a memory card. It is provided with an image sensor chip to capture images, as opposed to film used by traditional cameras. Besides this, a camera that is connected to your computer can also be called a digital camera.

It has photosensors to record light that enters the camera through the lens. When the light strikes the photosensors, each of the sensors returns the electrical current, which is used to create the images.

11) Paddle:

It is a simple input device that is widely used in games. It is a wheel that is held by hand and looks like a volume knob on a stereo that is used to increase or decrease the volume. Paddle moves or controls cursor or any other objects in the game in a back-and-forth motion. It is widely used as an alternative to the joystick. Besides this, the term paddle also refers to many handheld devices designed to control a function in an electronic device, computer, etc.

12) Steering wheel:

It is used as an input device in racing video games such as car racing games or in driving programs as virtual simulators to steer a vehicle. It works like the real steering wheel by allowing you to take a right or left turn. A steering wheel may be provided with acceleration and brake pedal devices and a mechanism for shifting gears. Thus, it makes racing games more adventurous and entertaining.

13) Gesture recognition devices:

These devices take human gestures as input. There are many such devices that respond to gestures. For example, Kinect is one such device that observes the movement of a player's body and interprets these movements as inputs to video games. This feature is also available in certain tablets and smartphones where you can perform certain tasks such as taking pictures using finger gestures such as swiping, pinching, etc.

14) Light Gun:

As the name suggests, it is a pointing input device that is designed to point at and shoot the targets on the screen in a video game, or arcade, etc. The light gun was used for the first time on the MIT Whirwind computer. When the gun is pointed at the target on the screen and the trigger is pulled, the screen goes blank for a fraction of a second. During this moment, the photodiode, which is present in the barrel, determines where the gun is pointed. For example, shooting ducks in a duck hunt game.

15) Touchpad:

It is usually found in laptops as a substitute for the mouse. It allows you to move or control the cursor on the screen using your finger. Just like a mouse, it also has two buttons for right and left click. Using the touchpad, you can perform all the tasks that you do with a mouse, such as selecting an object on the screen, copy, paste, delete, open a file or folder, and more.

16) Remote:

It is a hardware device designed to control the functioning of a device, e.g., a TV remote that can be used to change channels, increase or decrease the volume, from a distance without leaving the seat. The first cordless TV remote was invented by Dr. Robert Adler of Zenith in 1956. The remote sends the electromagnetic waves to communicate with the device. These waves can be infrared rays, radio waves, etc.

17) Touch screen:

It is the display screen of a device such as a smartphone, tablet, etc., that allows users to interact or provide inputs to the device by using their finger. Today, most of the electronic devices come with touchscreen as an alternative to a mouse for navigating a graphical user interface. For example, by touching, you can unlock your phone, open emails, open files, play videos, etc. Besides this, it is used in lots of devices such as Camera, Car GPS, Fitness machine, etc.

The concept of the touch screen was first introduced and published by E.A. Johnson in 1965. The first touch screen was developed at the beginning of the 1970s by CERN engineers Frank Beck and Bent Stumpe.

18) VR:

VR stands for virtual reality. It is an artificial or virtual environment which is generated by computers. A person can interact with virtual objects of this artificial environment using some input devices such as headsets, gloves, headphones, etc. For example, he or she can find himself or herself walking on a beach, watching a football match, walking in the sky, etc., without actually doing all this.

19) Webcam:

Any camera which is connected to a computer is called a webcam. The in-built camera provided on a computer can also be considered a webcam. It is an input device as it can take pictures, and can be used to record videos if required. The pictures and videos are stored in the computer memory and can be displayed on the screen if required. Although it works almost the same as the digital camera, it is different from a digital camera, as it is designed to take compact digital photos that can be uploaded easily on the webpages and shared with others through the internet.

20) Biometric Devices:

Biometrics refers to a process in which a person is identified through his or her biological features such as fingerprints, eye cornea, face structure, etc. It is done by using biometric devices, which can be of different types based on their scanning features and abilities, such as:

I) Face Scanner:

It is designed to identify a person by scanning his or her face. It takes the face measurements of a person. For example, the distance between eyes, nose, and mouth, etc., accordingly, it confirms the identity of a person. Besides this, it is smart enough to differentiate between a person's picture and the real person.

II) Hand Scanner:

The hand of a person can also be used to verify his or her identity as every person has a unique pattern of veins in the palm, just like fingerprints. This device takes advantage of this feature; it identifies a person by scanning the palm of his hand. It uses infrared light to scan veins' patterns and blood flowing in them. Palm is even more unique than fingerprints.

III) Fingerprint Scanner:

It scans the fingerprints to identify people or for biometric authentication. This device is developed, keeping in mind the fact that no two persons in the world can have the same fingerprints. It is widely used in companies as a fingerprint attendance system to mark the attendance of employees. This type of scanners captures the pattern of valleys and ridges found on a finger and store it in the memory or database. When you press your finger on the given space, it verifies the identity by using its pattern-matching software.

IV) Retina or Iris Scanner:

It scans the retina or iris of a person's eye to confirm the identity. This device is more secure than others as it is next to impossible to copy the retina or iris. It works by mapping the retina's blood vessel patterns of the eye. The blood vessels of retina absorb light more easily as well as can be identified with appropriate lighting.

In this scan, a beam of low-energy infrared light falls on the retina through the scanner's eyepiece. Then, the software captures the network of blood vessels in the retina and uses it to verify a person's identity.

V) Voice Scanner:

It records the voice of a person and digitizes it to create a distinctive voice print or template. The voiceprints are stored in the database, and are used to verify the voice of a person to confirm his or her identity. The person is required to speak in the normal or same voice that was used to create a voice template. It is not much reliable as it can be misused using a tape recording.

Computer Components

2021-07-08T09:30:00.000+05:30

Computer Components

There are 5 main computer components that are given below:

Input Devices
CPU
Output Devices
Primary Memory
Secondary Memory

The operations of computer components are given below:

Inputting: It is the process of entering raw data, instructions and information into the computer. It is performed with the help of input devices.
Storing: The computer has primary memory and secondary storage to store data and instructions. It stores the data before sending it to CPU for processing and also stores the processed data before displaying it as output.
Processing: It is the process of converting the raw data into useful information. This process is performed by the CPU of the computer. It takes the raw data from storage, processes it and then sends back the processed data to storage.
Outputting: It is the process of presenting the processed data through output devices like monitor, printer and speakers.
Controlling: This operation is performed by the control unit that is part of CPU. The control unit ensures that all basic operations are executed in a right manner and sequence.

Types of Computer

2021-07-08T09:16:00.003+05:30

Types of Computer

We can categorize computer in two ways: on the basis of data handling capabilities and size.

On the basis of data handling capabilities, the computer is of three types:

1) Analogue Computer

Analogue computers are designed to process analogue data. Analogue data is continuous data that changes continuously and cannot have discrete values. We can say that analogue computers are used where we don't need exact values always such as speed, temperature, pressure and current.

Analogue computers directly accept the data from the measuring device without first converting it into numbers and codes. They measure the continuous changes in physical quantity and generally render output as a reading on a dial or scale. Speedometer and mercury thermometer are examples of analogue computers.

Advantages of using analogue computers:

It allows real-time operations and computation at the same time and continuous representation of all data within the rage of the analogue machine.
In some applications, it allows performing calculations without taking the help of transducers for converting the inputs or outputs to digital electronic form and vice versa.
The programmer can scale the problem for the dynamic range of the analogue computer. It provides insight into the problem and helps understand the errors and their effects.

Types of analogue computers:

Slide Rules: It is one of the simplest types of mechanical analogue computers. It was developed to perform basic mathematical calculations. It is made of two rods. To perform the calculation, the hashed rod is slid to line up with the markings on another rod.
Differential Analysers: It was developed to perform differential calculations. It performs integration using wheel-and-disc mechanisms to solve differential calculations.
Castle Clock: It was invented by Al-Jarazi. It was able to save programming instructions. Its height was around 11 feet and it was provided with the display of time, the zodiac, and the solar and lunar orbits. This device also could allow users to set the length of the day as per the current season.
Electronic Analogue Computer: In this type of analogue computer, electrical signals flow through capacitors and resistors to simulate physical phenomena. Here, the mechanical interaction of components does not take place. The voltage of the electrical signal generates the appropriate displays.

2) Digital Computer

Digital computer is designed to perform calculations and logical operations at high speed. It accepts the raw data as input in the form of digits or binary numbers (0 and 1) and processes it with programs stored in its memory to produce the output. All modern computers like laptops, desktops including smartphones that we use at home or office are digital computers.

Advantages of digital computers:

It allows you to store a large amount of information and to retrieve it easily whenever you need it.
You can easily add new features to digital systems more easily.
Different applications can be used in digital systems just by changing the program without making any changes in hardware
The cost of hardware is less due to the advancement in the IC technology.
It offers high speed as the data is processed digitally.
It is highly reliable as it uses error correction codes.
Reproducibility of results is higher as the output is not affected by noise, temperature, humidity, and other properties of its components.

3) Hybrid Computer

Hybrid computer has features of both analogue and digital computer. It is fast like an analogue computer and has memory and accuracy like digital computers. It can process both continuous and discrete data. It accepts analogue signals and convert them into digital form before processing. So, it is widely used in specialized applications where both analogue and digital data is processed. For example, a processor is used in petrol pumps that converts the measurements of fuel flow into quantity and price. Similarly, they are used in airplanes, hospitals, and scientific applications.

Advantages of using hybrid computers:

Its computing speed is very high due to the all-parallel configuration of the analogue subsystem.
It produces precise and quick results that are more accurate and useful.
It has the ability to solve and manage big equation in real-time.
It helps in the on-line data processing.

On the basis of size, the computer can be of five types:

1) Supercomputer

Supercomputers are the biggest and fastest computers. They are designed to process huge amount of data. A supercomputer can process trillions of instructions in a second. It has thousands of interconnected processors.

Supercomputers are particularly used in scientific and engineering applications such as weather forecasting, scientific simulations and nuclear energy research. The first supercomputer was developed by Roger Cray in 1976.

Characteristics or applications of supercomputers:

It has the ability to decrypt your password to enhance protection for security reasons.
It produces excellent results in animations.
It is used for virtual testing of nuclear weapons and critical medical tests.
It can study and understand climate patterns and forecast weather conditions. It can run in NOAA's system (National Oceanic and Atmospheric Administration) that can execute any type of simple and logical data.
It helps in designing the flight simulators for pilots at the beginner level for their training.
It helps in extracting useful information from data storage centres or cloud system. For example, in insurance companies.
It has played a vital role in managing the online currency world such as stock market and bitcoin.
It helps in the diagnosis of various critical diseases and in producing accurate results in brain injuries, strokes, etc.
It helps in scientific research areas by accurately analysing data obtained from exploring the solar system, satellites, and movement of Earth.
It also used in a smog control system where it predicts the level of fog and other pollutants in the atmosphere.

2) Mainframe computer

Mainframe computers are designed to support hundreds or thousands of users simultaneously. They can support multiple programs at the same time. It means they can execute different processes simultaneously. These features of mainframe computers make them ideal for big organizations like banking and telecom sectors, which need to manage and process high volume of data.

Mainframe computers are designed to support hundreds or thousands of users simultaneously. They can support multiple programs at the same time. It means they can execute different processes simultaneously. These features of mainframe computers make them ideal for big organizations like banking and telecom sectors, which need to manage and process a high volume of data that requires integer operations such as indexing, comparisons, etc.

Characteristics of Mainframe Computers:

It can process huge amount of data, e.g. millions of transactions in a second in the banking sector.
It has a very long life. It can run smoothly for up to 50 years after proper installation.
It gives excellent performance with large scale memory management.
It has the ability to share or distribute its workload among other processors and input/output terminals.
There are fewer chances of error or bugs during processing in mainframe computers. If any error occurs it can fix it quickly without affecting the performance.
It has the ability to protect the stored data and other ongoing exchange of information and data.

Applications of mainframe computers:

In health care, it enabled hospitals to maintain a record of their millions of patients in order to contact them for treatment or related to their appointment, medicine updates or disease updates.
In the field of defence, it allows the defence departments to share a large amount of sensitive information with other branches of defence.
In the field of education, it helps big universities to store, manage and retrieve data related to their courses, admissions, students, teachers, employees and affiliated schools and colleges.
In the retail sector, the retail companies that have a huge customer base and branches use mainframe computers to handle and execute information related to their inventory management, customer management, and huge transactions in a short duration.

3) Miniframe or Minicomputer

It is a midsize multiprocessing computer. It consists of two or more processors and can support 4 to 200 users at one time. Miniframe computers are used in institutes and departments for tasks such as billing, accounting and inventory management. A minicomputer lies between the mainframe and microcomputer as it is smaller than mainframe but larger than a microcomputer.

Characteristics of miniframe or minicomputer:

It is light weight that makes it easy to carry and fit anywhere.
It is less expensive than mainframe computers.
It is very fast compared to its size.
It remains charged for a long time.
It does not require a controlled operational environment.

Applications of minicomputers:

A minicomputer is mainly used to perform three primary functions, which are as follows:

Process control: It was used for process control in manufacturing. It mainly performs two primary functions that are collecting data and feedback. If any abnormality occurs in the process, it is detected by the minicomputer and necessary adjustments are made accordingly.
Data management: It is an excellent device for small organizations to collect, store and share data. Local hospitals and hotels can use it to maintain the records of their patients and customers respectively.
Communications Portal: It can also play the role of a communication device in larger systems by serving as a portal between a human operator and a central processor or computer.

4) Workstation

Workstation is a single user computer that is designed for technical or scientific applications. It has a faster microprocessor, a large amount of RAM and high speed graphic adapters. It generally performs a specific job with great expertise; accordingly, they are of different types such as graphics workstation, music workstation and engineering design workstation.

Characteristics of workstation computer:

It is a high-performance computer system designed for a single user for business or professional use.
It has larger storage capacity, better graphics, and more powerful CPU than a personal computer.
It can handle animation, data analysis, CAD, audio and video creation and editing.

Any computer that has the following five features, can be termed as a workstation or can be used as a workstation.

Multiple Processor Cores: It has more processor cores than simple laptops or computers.
ECC RAM: It is provided with Error-correcting code memory that can fix memory errors before they affect the system's performance.
RAID (Redundant Array of Independent Disks): It refers to multiple internal hard drives to store or process data. RAID can be of different types, for example, there can be multiple drives to process data or mirrored drives where if one drive does not work than other starts functioning.
SSD: It is better than conventional hard-disk drives. It does not have moving parts, so the chances of physical failure are very less.
Optimized, Higher end GPU: It reduces the load on CPU. E.g., CPU has to do less work while processing the screen output.

5) Microcomputer

Microcomputer is also known as a personal computer. It is a general-purpose computer that is designed for individual use. It has a microprocessor as a central processing unit, memory, storage area, input unit and output unit. Laptops and desktop computers are examples of microcomputers. They are suitable for personal work that may be making an assignment, watching a movie, or at office for office work.

Characteristics of a microcomputer:

It is the smallest in size among all types of computers.
A limited number of software can be used.
It is designed for personal work and applications. Only one user can work at a time.
It is less expansive and easy to use.
It does not require the user to have special skills or training to use it.
Generally, comes with single semiconductor chip.
It is capable of multitasking such as printing, scanning, browsing, watching videos, etc.

History of Computers

2021-07-08T08:45:00.004+05:30

History of Computers

The first counting device was used by the primitive people. They used sticks, stones and bones as counting tools. As human mind and technology improved with time more computing devices were developed. Some of the popular computing devices starting with the first to recent ones are described below;

Abacus

The history of computer begins with the birth of abacus which is believed to be the first computer. It is said that Chinese invented Abacus around 4,000 years ago.

It was a wooden rack which has metal rods with beads mounted on them. The beads were moved by the abacus operator according to some rules to perform arithmetic calculations. Abacus is still used in some countries like China, Russia and Japan. An image of this tool is shown below;

Abacus

Napier's Bones

It was a manually-operated calculating device which was invented by John Napier (1550-1617) of Merchiston. In this calculating tool, he used 9 different ivory strips or bones marked with numbers to multiply and divide. So, the tool became known as "Napier's Bones. It was also the first machine to use the decimal point.

Napier's Bones

Pascaline

Pascaline is also known as Arithmetic Machine or Adding Machine. It was invented between 1642 and 1644 by a French mathematician-philosopher Biaise Pascal. It is believed that it was the first mechanical and automatic calculator.

Pascal invented this machine to help his father, a tax accountant. It could only perform addition and subtraction. It was a wooden box with a series of gears and wheels. When a wheel is rotated one revolution, it rotates the neighboring wheel. A series of windows is given on the top of the wheels to read the totals. An image of this tool is shown below;

Pascaline

Stepped Reckoner or Leibnitz wheel

It was developed by a German mathematician-philosopher Gottfried Wilhelm Leibnitz in 1673. He improved Pascal's invention to develop this machine. It was a digital mechanical calculator which was called the stepped reckoner as instead of gears it was made of fluted drums. See the following image;

Stepped Reckoner or Leibnitz wheel

Difference Engine

In the early 1820s, it was designed by Charles Babbage who is known as "Father of Modern Computer". It was a mechanical computer which could perform simple calculations. It was a steam driven calculating machine designed to solve tables of numbers like logarithm tables.

Difference Engine

Analytical Engine

This calculating machine was also developed by Charles Babbage in 1830. It was a mechanical computer that used punch-cards as input. It was capable of solving any mathematical problem and storing information as a permanent memory.

Analytical Engine

Tabulating Machine

It was invented in 1890, by Herman Hollerith, an American statistician. It was a mechanical tabulator based on punch cards. It could tabulate statistics and record or sort data or information. This machine was used in the 1890 U.S. Census. Hollerith also started the Hollerith?s Tabulating Machine Company which later became International Business Machine (IBM) in 1924.

Tabulating Machine

Differential Analyzer

It was the first electronic computer introduced in the United States in 1930. It was an analog device invented by Vannevar Bush. This machine has vacuum tubes to switch electrical signals to perform calculations. It could do 25 calculations in few minutes.

Differential Analyzer

Mark I

The next major changes in the history of computer began in 1937 when Howard Aiken planned to develop a machine that could perform calculations involving large numbers. In 1944, Mark I computer was built as a partnership between IBM and Harvard. It was the first programmable digital computer.

Mark I

Generations of Computers

A generation of computers refers to the specific improvements in computer technology with time. In 1946, electronic pathways called circuits were developed to perform the counting. It replaced the gears and other mechanical parts used for counting in previous computing machines.

In each new generation, the circuits became smaller and more advanced than the previous generation circuits. The miniaturization helped increase the speed, memory and power of computers. There are five generations of computers which are described below;

First Generation Computers

The first generation (1946-1959) computers were slow, huge and expensive. In these computers, vacuum tubes were used as the basic components of CPU and memory. These computers were mainly depended on batch operating system and punch cards. Magnetic tape and paper tape were used as output and input devices in this generation;

Some of the popular first generation computers are;

ENIAC ( Electronic Numerical Integrator and Computer)
EDVAC ( Electronic Discrete Variable Automatic Computer)
UNIVACI( Universal Automatic Computer)
IBM-701
IBM-650

Second Generation Computers

The second generation (1959-1965) was the era of the transistor computers. These computers used transistors which were cheap, compact and consuming less power; it made transistor computers faster than the first generation computers.

In this generation, magnetic cores were used as the primary memory and magnetic disc and tapes were used as the secondary storage. Assembly language and programming languages like COBOL and FORTRAN, and Batch processing and multiprogramming operating systems were used in these computers.

Some of the popular second generation computers are;

IBM 1620
IBM 7094
CDC 1604
CDC 3600
UNIVAC 1108

Third Generation Computers

The third generation computers used integrated circuits (ICs) instead of transistors. A single IC can pack huge number of transistors which increased the power of a computer and reduced the cost. The computers also became more reliable, efficient and smaller in size. These generation computers used remote processing, time-sharing, multi programming as operating system. Also, the high-level programming languages like FORTRON-II TO IV, COBOL, PASCAL PL/1, ALGOL-68 were used in this generation.

Some of the popular third generation computers are;

IBM-360 series
Honeywell-6000 series
PDP(Personal Data Processor)
IBM-370/168
TDC-316

Fourth Generation Computers

The fourth generation (1971-1980) computers used very large scale integrated (VLSI) circuits; a chip containing millions of transistors and other circuit elements. These chips made this generation computers more compact, powerful, fast and affordable. These generation computers used real time, time sharing and distributed operating system. The programming languages like C, C++, DBASE were also used in this generation.

Some of the popular fourth generation computers are;

DEC 10
STAR 1000
PDP 11
CRAY-1(Super Computer)
CRAY-X-MP(Super Computer)

Fifth Generation Computers

In fifth generation (1980-till date) computers, the VLSI technology was replaced with ULSI (Ultra Large Scale Integration). It made possible the production of microprocessor chips with ten million electronic components. This generation computers used parallel processing hardware and AI (Artificial Intelligence) software. The programming languages used in this generation were C, C++, Java, .Net, etc.

Some of the popular fifth generation computers are;

Desktop
Laptop
NoteBook
UltraBook
ChromeBook

What is BIOS?

2021-07-07T22:24:00.002+05:30

What is BIOS?

BIOS is a program, stands for basic input/output system, which is stored in nonvolatile memory like ROM (Read Only Memory) or flash memory that allows you to set up and access your computer system at the greatest basic level. Although there is no need for most people to mess with the BIOS on a computer, it can be better to know about BIOS. It is found on motherboards that are a pre-installed program on Windows-based computers that executes when a computer is powered up. Before an OS is loaded, the CPU accesses the basic input/output system (BIOS). Then, the next function of BIOS is to examine all the hardware connections and detects all your devices.

The main function of BIOS is to set up hardware and start an OS, and it contains generic code that is needed to control display screens, the keyboard, and other functions. The BIOS is built-in software that manages the hard drives and cannot live on one. It cannot reside in the RAM (Random Access Memory) as it is accessible before the computer system boots up. Actually, it lives on the ROM of the computer system, and mainly it is located on EPROM (erasable programmable read-only memory) chip. Therefore, the CPU accesses the EPROM when you turn on the computer and provides control to the BIOS.

The primary intention of designing the BIOS system is to function with numerous devices that led to making a complimentary system chipset. There are some functions contained by the BIOS library that operates and controls system peripherals, and they can be initiated through external software.

Users can perform different functions by using the BIOS user interface, which is discussed below:

Users can perform hardware configuration
They can select boot drives
They can set the system clock
The BIOS allows users to enable and disable certain system components
To BIOS user interface function, it provides set password prompts for secured access

The BIOS works as an intermediary between the I/O devices and the CPU and is used after the computer has booted up. The BIOS works as an intermediary between the I/O devices and the CPU and is used after the computer has booted up. Your operating system and programs do not need to know the details about the I/O devices connected to your system because of the BIOS. You can change these settings accordingly with the help of entering the BIOS setup at the time of your system starts up. Furthermore, if you want to access the BIOS setup, you can hold down the DELETE or F2 key when your computer starts up.

BIOS is stored in rewritable memory in some modern PCs, which allow information to be replaced or rewritten. Such content rewriting is executed with the help of a special program offered by system manufacturers.

BIOS Availability

The BIOS software is available in all modern computer motherboards. As the BIOS is a part of the motherboard; therefore, the BIOS's access and configuration on PCs are independent of any type of operating system. The BIOS is not dependent on anyone that means it does not matter which types of an operating system is running on the computer like Windows 7, Windows 8, Windows 10, Windows XP, Linux, Windows Vista, Unix, or no operating system at all, BIOS functions outside of the operating system environment.

What is included in a BIOS?

The directions to load basic computer hardware are included in BIOS software. A test is also included within it that is referred to as a POST (Power-On Self-Test). The POST helps the computer to boot up properly with verifying the computer meets requirements. Your computer produces various forms of beeps if the POST test fails at the time of test.

Functions of BIOS

The BIOS has different instructions that are required to load the hardware, and it is responsible for loading the operating system. The major functions of a Basic input/output system (BIOS) are discussed below:

BIOS Power on Self-Test (POST): It ensures the proper functioning of the computer hardware as it is a built-in diagnostic program that. In the system, it verifies the computer meets the necessary parts and functionality. POST does this function efficiently. It ensures that the computer is loading tasks successfully, such as the use of memory, a keyboard, and other parts when it starts up. If the POST test fails at the time of test, the computer provides a combination of beeps to display the error type, and the system continues to boot when the POST test is passed completely.
Once the self-test has been passed, and the basic instructions have been loaded, the computer starts to load the OS from one of the connected drives to the system. The BIOS settings can also be changed by the computer users with the help of a configuration screen on the computer. The BIOS information can also be stored on the flash memory, which can be updated by computer users after releasing an update by vendors. BIOS actually can be located in between the external devices and the computer because its name describes that it is used for reading and writing to and hard disk and floppy disc, displaying values on the screen, reading the keystroke, etc.
Bootstrap Loader: The BIOS recognizes and locates the operating system when the POST running successfully. The program bootstrap loader is contained by BIOS, which searches and starts the OS boot program. When BIOS detects one, it transfers access to Operating System that is known as booting.
BIOS drivers: BIOS drivers are stored in the non-volatile memory, whose primary function is to supply basic computer hardware information.
BIOS Setup Utility Program: It is a configuration software, also known as CMOS setup, that allows users to configure hardware settings as well as device settings, time and date, computer password. The NVRAM, non-volatile memory, is used to store settings of memory, disk types, and information about the computer system; this information is not stored in the BIOS chip

The users run the BIOS setup program during the installation of a system and input the correct parameters. The CMOS (Complementary metal-oxide-semiconductor) is a required material to construct NVRAM. These CMOS chips store and maintain data on very low values of current. Therefore, the system's configurations are also called CMOS settings. With the help of using a capacitor, maintaining the battery backup, or by a battery built into the NVRAM chip, CMOS settings can be maintained. Additionally, a system clock is also included in this chip. The setting remains for a short period of time if there is no battery. And there is a need to reset the system. Through its BIOS set up program is protected as there is loss of BIOS password.

With computers, BIOS come in-built as firmware on a chip on the motherboard. In contrast, an operating system such as iOS or Windows can be installed by the user or pre-installed by the vendor or manufacturer.

When BIOS boots up a computer, it verifies the computer meets the necessary attachments to boot up. The files are contained by any piece of hardware that needs for a computer to start up, this piece of hardware is known as a boot device.

Different types of BIOS

The BIOS screen is seen by every PC user, it does not matter he knows it or not each time he turns on his computer system. The computer's manufacturer displays the screen is called the Basic Input/output System (BIOS). The BIOS has mainly two types, which are as follows:

UEFI: The UEFI can accommodate 2.2 TB or larger drives, which stands for Unified Extensible Firmware Interface. It handles drives with the help of using the Master Boot Record instead of GPT technology, the more modern GUID Partition Table. Furthermore, Apple's Mac PCs have never used the BIOS.
Legacy BIOS: The Legacy BIOS was used in older motherboards to turn the PC on. Legacy BIOSes have limitations as they have no ability to handle or recognize drives bigger than 2.1 TB. However, it controls how the CPU and the components communicate with each other.

BIOS vs UEFI

Most probably, you will see UEFI rather than the BIOS in most modern computers. But what are the differences between both UEFI and BIOS? It can be difficult to differentiate both because they almost perform the same function. UEFI is the same as BIOS, stands for Unified Extensible Firmware Interface, and acts as an intermediate program between the hardware and the OS.

As compared to BIOS, UEFI offers more features and can be extensively customized. In order to load the operating system, it does not need a separate program of a bootloader. It has the ability to manage hard drives that can be exceeded two Terabytes as it offers native support GPT, and BIOS is unable to provide this.

Upgrading a BIOS

Often, it is discovered that when the computer needs to be upgraded with latest hardware, it does not support all the features of the latest hardware. It needs to be upgraded hardware like more memory, a larger hard drive, or a new video card. Upgrading the BIOS chip is an easier solution to this problem. Generally, to upgrade BIOS on the system, the files and information are available on the computer's or motherboard maker's Web site.

Unluckily, it is most important to know that upgrading the BIOS can be a drastic step. If you are going to upgrade the BIOS, you will be better to back up all of your data from the hard drive. Also, make sure there is a recovery jumper that makes you capable of recovering the original BIOS. Although upgrading the BIOS is trouble-free, it is possible for the by upgrading BIOS the system can be computer unusable, damage or destroy the BIOS chip.

A brief history of BIOS

The term BIOS (Basic Input/output System) first appeared in the CP/M operating system in 1975 and was created by Gary Kildall. It was used to describe the machine-specific part of CP/M loaded during the boot time. These ideas were adopted by Microsoft DOS in the first versions of DOS, which included similar. The files used in CP/M were very close to COM and.SYS files.

The PC's BIOS was held on PROM or ROM chips that were placed on the computer's motherboard through the early 1990s. Some companies, such as Phoenix Technologies, reversed the BIOS originally proprietary to the IBM PC, creating compatible systems. Also, in the mid-1990s, the BIOS was shifted to being stored on EEPROM chips or flash drives on the computer, as to update the BIOS, and demand for complexity increased. In modern times, some computers can have the BIOS, which size can be more than 16 megabytes.

The System BIOS was divided by IBM into real- and protected-mode portions when the PS/2 machines were introduced. The real-mode portion was mainly responsible for offering compatibility with existing OS like DOS, that's why it's named was CBIOS, while new interfaces were provided by ABIOS that was especially ideal for multitasking operating systems such as OS/2.

How to check the version of BIOS?

You are required to access the BIOS setup if you want to check the type or version of BIOS on your computer system. You will see the BIOS version or type on the main BIOS display such as Phoenix, Award, AMI, and more other kinds of the BIOS.

BIOS security

BIOS security somewhere is a unique component of cybersecurity. However, there is still a need to manage it because there are various hackers who can run malicious code on the OS, which can be more harmful. In 2017, inside a motherboard's UEFI, how modern BIOS security flaws could enable ransomware programs it showed by security group Cylance. And other PCs get the benefit of BIOS vulnerabilities.

BIOS manufacturers

In the beginning, BIOS was fundamentally owned by IBM. However, IBM's original version was reverse-engineered by some other companies like Phoenix Technologies to create their own. For doing that, other companies have permission to create clones of the IBM PC by Phoenix. Also, an important thing that they can create non-IBM computers that work with BIOS. Compaq was one company that did this. In modern times, there are various manufacturers of the motherboard with BIOS chips; some are as follows:

Foxconn
AMI
Hewlett Packard (HP)
Ricoh
Asus

It may be very important to know about the motherboard manufacturer as users sometimes need to update their BIOS and chipset drivers. The operating system functions with other devices in the computer through the drivers. For example, a video card to the most recent versions. When you update drivers, the patch can cause recent BIOS-level security vulnerabilities, or computer performance can be improved.

Does Macs have BIOS?

The operating system (OS) has a BIOS; it is a misperception by Mac users as Macs do not use EFI. Traditionally, they have used G4 Mac Minis, eMacs, iBooks, iBooks, Dual G5s, and OpenFirmware for PowerBooks, etc. There will be an audible chime if the sound is turned on.

Computer Virus

2021-07-07T22:15:00.004+05:30

Computer Virus

Computer viruses are unwanted software programs or pieces of code that interfere with the functioning of the computer. They spread through contaminated files, data, and insecure networks. Once it enters your system, it can replicate to produce copies of itself to spread from one program to another program and from one infected computer to another computer. So, we can say that it is a self-replicating computer program that interferes with the functioning of the computer by infecting files, data, programs, etc.

There are many antiviruses, which are programs that can help you protect your machine from viruses. It scans your system and cleans the viruses detected during the scan. Some of the popular antiviruses include Avast, Quickheal, McAfee, Kaspersky, etc.

Types of Computer Virus:

Overwrite Virus:

It is the simplest computer virus that overwrites the code of the host computer system's file with its own malicious code. The content of the infected file is replaced partially or completely without changing the size of the file. Thus, it destroys the original program code by overwriting it with its defective code. The infected files must be deleted or replaced with a new copy as this virus cannot be removed or disinfected.

Append Virus:

As the name suggests, this virus appends its malicious code to the end of the host program's file. After that, it alters the file's header in a way that the file's header is redirected to the start of the malicious code of the append virus. Thus, this code is executed each time the program runs. However, it does not destroy the host program; rather, it modifies it in a way that it holds the virus code and enables the code to run itself.

Macro Virus

Macro virus alters or infects the macros of a document or data file. It is embedded as a macro in a document and adds its codes to the macros of the document. The virus spreads when infected documents or data files are opened in other computers.

It also spreads through software programs, which execute macros such as Ms Word, Ms Excel. Each time a document is opened using these programs, other related documents will also get infected.

The first macro virus, which was named concept, spread through emails with attached Ms Word documents. It infected MsWord 6.0 and Ms Word 95 documents, which were saved using Save As option. Fortunately, it did not cause any harm, except for displaying a message on the screen.

Boot Virus

Boot virus or boot sector virus alters the boot sector program stored in the hard disk or any other storage device such as floppy disks. It replaces the boot sector program with its own malicious version. It infects the computer only when it is used to boot up the computer. If it enters after the boot-up process, it will not infect the computer. For example, if someone forgets to remove the infected floppy disk when the pc is turned off and then turns on this pc, it runs the infected boot sector program during the booting process.

Usually, it enters into your system through corrupt media files, infected storage devices, and insecure computer networks. The spread of this virus is very rare these days due to the decline in the use of floppy disk and use of boot-sector safeguards in the present-day operating systems.

Resident Virus

The resident virus stays permanently in the primary memory (RAM) of the computer. When you start the computer, it becomes active and corrupts the files and programs running on the computer.

Non-resident Virus:

Unlike the resident virus, the non-resident virus does not reside in the memory of a computer. So, it is not executed from the computer's memory. For example, executable viruses.

Multipartite Virus

Multipartite virus spreads and infects in multiple ways. It infects both the boot sector and the executable files stored on the hard drive simultaneously. When you turn on a computer, the boot sector virus is triggered as it latches on to the hard drive, which has the data for starting up the computer. Once it is triggered, the program files also get infected.

File Infector Virus

It is one of the commonly found computer viruses. It mainly infects the executable files; the files with .com or .exe extensions. The virus becomes active when the infected file is executed. The active virus overwrites the file partially or completely. Thus it may destroy the original file partially or completely.

Computer Worm

Computer worm is similar to a virus but is technically different from the virus. It can replicate and spread like a virus, but unlike viruses, it does not need a host program to spread. Being able to self-replicate it can produce multiple copies of itself. It spreads through networks such as an email sent to an infected email id can infect your system with a computer worm.

Trojan Horse

Trojan horse is a malware like a virus or a worm, but it is technically different from both. It can't replicate like virus and worm. Trojan horse hides itself in a program. Once you install any such program, the trojan horse enters into your computer. It can provide unauthorized access to your computer, send your files to other computers, and may delete files or can make other unwanted changes in your computer.

Cavity virus:

It is also known as a spacefiller virus. As the name suggests, this virus tends to install itself by occupying the empty sections of a file. It is not easy to detect this virus as it fills the empty spaces without changing the size of the file.

CMOS Virus:

It infects the CMOS, which stands for complementary metal-oxide semiconductor and is a memory chip that contains the system configuration. This virus can erase or reset the system configuration.

Companion Virus:

It resides itself in a file whose name is similar to another program file, which is executed normally. When the program file is executed, the virus gets activated and performs malicious steps such as deleting the files on your computer hard drive. Globe virus is a first known companion virus, which was found in 1992.

Encrypted Virus:

It encrypts its payload to make its detection more difficult. It comprises two parts: an encrypted virus body and a decryptor, which decrypts the virus when it is executed. After decryption, the virus can execute itself in order to replicate and become a resident. Furthermore, it is different from cryptolocker, which is a computer virus that encrypts the hard drive data and holds it for ransom.

Executable Virus:

It is a non-resident computer virus, which resides in an executable file. Whenever the infected file is executed, it infects the other files.

Polymorphic Virus:

It creates its thousands of copies itself; in each copy, it changes the sequence and byte values to evade detection by antivirus software. Even the best antiviruses may not be able to detect this virus. Polymorphic viruses affect data types and functions and generally spread through spam, infected sites, and while using other malware.

Rabbit Virus:

It is also known as wabbit, a fork bomb. It is capable of creating new processes, and each of the new process further creates new processes. This process continues until this virus utilizes all the available resources in the system and system falls short of resources. It may cause the target system to slow down and crash. For example, it is like an Infinite loop that repeatedly creates processes that consume lots of CPU cycles and operating system resources.

Stealth Virus:

It is a hidden computer virus, which specifically attacks operating system processes. It usually hides itself in partitions, files or boot sectors and is capable of going unnoticed during antivirus or anti-malware scans, i.e., it can avoid detection intentionally.

Symptoms of a Computer Virus:

There are many warning signs or symptoms which show that a computer is infected with a virus, some of which are as follows:

Slow computer performance: The machine may work slowly, e.g., it will take more time to open or shut down the computer or while opening a file, document, computer application, etc. The operating system and internet speed may get slow.
Frequent pop-ups: A virus may cause unusual frequent pop-ups on your window.
Hard Drive issue: The hard drive may exhibit unusual high activity even when it is not in use. It may cause unwanted changes to your hard drive and may freeze or crash this device.
Frequent crashes: One may experience frequent sudden system crashes while playing games, watching videos, or doing some other work using the infected system. A blue screen appears when it crashes.
Unknown programs: Unwanted programs may open or start automatically when you start your computer. You can see these programs in your computer's list of active applications. Sometimes, the window shuts down unexpectedly without any reason.
Unusual activities: Your machine may perform differently, such as you may not be able to log into your accounts, to delete the corrupt files, and Blue Screen of Death (BSOD) may appear frequently, and more. Furthermore, the hardware, software, or OS may start malfunctioning leading to crashing the system abruptly.
Impaired security solutions: Sometimes, security measures taken by you, such as antivirus may not work smoothly due to virus attack on your computer.
Network issue: Sometimes, you experience high network activity even if you are not connected to the internet and vice versa.
Unnecessary advertisement: We often see advertisements while browsing, but if you see them even when you are not browsing, it may indicate a virus on your computer.
Display problems: You may experience different colors in your display if your computer is affected by a virus.
Affected Applications: Some viruses are developed to affect specific applications. Consequently, some applications may not work on your computer if it is infected.
Blocked by Antivirus Sites: An antivirus site may deny access to a computer that is infected by a virus.
Dialog Boxes: Many dialog boxes keep appearing suddenly on your screen.
Printer Issues: A printer attached to an infected computer may print documents without getting any command or in an inappropriate manner.
Changed Homepage: Your home page may get changed without any effort from your side. For example, you may see a new toolbar on your screen, and you may be redirected to a different web address instead of the page visited by you initially.
Strange messages: One may see strange messages on a computer screen such as error messages, e.g., "cannot rename "folder" as a folder already exists with this name

Java

2021-07-07T22:00:00.005+05:30

What is Java

Java is a programming language and a platform. Java is a high level, robust, object-oriented and secure programming language.

Java was developed by Sun Microsystems (which is now the subsidiary of Oracle) in the year 1995. James Gosling is known as the father of Java. Before Java, its name was Oak. Since Oak was already a registered company, so James Gosling and his team changed the Oak name to Java.

Platform: Any hardware or software environment in which a program runs, is known as a platform. Since Java has a runtime environment (JRE) and API, it is called a platform.

Application

According to Sun, 3 billion devices run Java. There are many devices where Java is currently used. Some of them are as follows:

Desktop Applications such as acrobat reader, media player, antivirus, etc.
Web Applications such as irctc.co.in, javatpoint.com, etc.
Enterprise Applications such as banking applications.
Mobile
Embedded System
Smart Card
Robotics
Games, etc.

Types of Java Applications

There are mainly 4 types of applications that can be created using Java programming:

1) Standalone Application

Standalone applications are also known as desktop applications or window-based applications. These are traditional software that we need to install on every machine. Examples of standalone application are Media player, antivirus, etc. AWT and Swing are used in Java for creating standalone applications.

2) Web Application

An application that runs on the server side and creates a dynamic page is called a web application. Currently, Servlet, JSP, Struts, Spring, Hibernate, JSF, etc. technologies are used for creating web applications in Java.

3) Enterprise Application

An application that is distributed in nature, such as banking applications, etc. is called enterprise application. It has advantages of the high-level security, load balancing, and clustering. In Java, EJB is used for creating enterprise applications.

4) Mobile Application

An application which is created for mobile devices is called a mobile application. Currently, Android and Java ME are used for creating mobile applications.

Java Platforms / Editions

There are 4 platforms or editions of Java:

1) Java SE (Java Standard Edition)

It is a Java programming platform. It includes Java programming APIs such as java.lang, java.io, java.net, java.util, java.sql, java.math etc. It includes core topics like OOPs, String, Regex, Exception, Inner classes, Multithreading, I/O Stream, Networking, AWT, Swing, Reflection, Collection, etc.

2) Java EE (Java Enterprise Edition)

It is an enterprise platform which is mainly used to develop web and enterprise applications. It is built on the top of the Java SE platform. It includes topics like Servlet, JSP, Web Services, EJB, JPA, etc.

3) Java ME (Java Micro Edition)
It is a micro platform which is mainly used to develop mobile applications.

4) JavaFX

It is used to develop rich internet applications. It uses a light-weight user interface API.

Python

2021-07-07T20:56:00.003+05:30

What is Python

Python is a general purpose, dynamic, high-level, and interpreted programming language. It supports Object Oriented programming approach to develop applications. It is simple and easy to learn and provides lots of high-level data structures.

Python is easy to learn yet powerful and versatile scripting language, which makes it attractive for Application Development.

Python's syntax and dynamic typing with its interpreted nature make it an ideal language for scripting and rapid application development.

Python supports multiple programming pattern, including object-oriented, imperative, and functional or procedural programming styles.

Python is not intended to work in a particular area, such as web programming. That is why it is known as multipurpose programming language because it can be used with web, enterprise, 3D CAD, etc.

We don't need to use data types to declare variable because it is dynamically typed so we can write a=10 to assign an integer value in an integer variable.

Python makes the development and debugging fast because there is no compilation step included in Python development, and edit-test-debug cycle is very fast.

Python History

Python was invented by Guido van Rossum in 1991 at CWI in Netherland. The idea of Python programming language has taken from the ABC programming language or we can say that ABC is a predecessor of Python language.

There is also a fact behind the choosing name Python. Guido van Rossum was a fan of the popular BBC comedy show of that time, "Monty Python's Flying Circus". So he decided to pick the name Python for his newly created programming language.

Python has the vast community across the world and releases its version within the short period.

Why learn Python?

Python provides many useful features to the programmer. These features make it most popular and widely used language. We have listed below few-essential feature of Python.

Easy to use and Learn
Expressive Language
Interpreted Language
Object-Oriented Language
Open Source Language
Extensible
Learn Standard Library
GUI Programming Support
Integrated
Embeddable
Dynamic Memory Allocation
Wide Range of Libraries and Frameworks

Where is Python used?

Python is a general-purpose, popular programming language and it is used in almost every technical field. The various areas of Python use are given below.

Data Science
Date Mining
Desktop Applications
Console-based Applications
Mobile Applications
Software Development
Artificial Intelligence
Web Applications
Enterprise Applications
3D CAD Applications
Machine Learning
Computer Vision or Image Processing Applications.
Speech Recognitions
Python Popular Frameworks and Libraries
Python has wide range of libraries and frameworks widely used in various fields such as machine learning, artificial intelligence, web applications, etc. We define some popular frameworks and libraries of Python as follows.
- Web development (Server-side) - Django Flask, Pyramid, CherryPy
- GUIs based applications - Tk, PyGTK, PyQt, PyJs, etc.
- Machine Learning - TensorFlow, PyTorch, Scikit-learn, Matplotlib, Scipy, etc.
- Mathematics - Numpy, Pandas, etc.

Software

2021-07-07T20:53:00.007+05:30

Software

Software, which is abbreviated as SW or S/W, is a set of programs that enables the hardware to perform a specific task. All the programs that run the computer are software. The software can be of three types: system software, application software, and programming software.

1) System Software

The system software is the main software that runs the computer. When you turn on the computer, it activates the hardware and controls and coordinates their functioning. The application programs are also controlled by system software. An operating system is an example of system software.

i) Operating System:

An operating system is the system software that works as an interface to enable the user to communicate with the computer. It manages and coordinates the functioning of hardware and software of the computer. The commonly used operating systems are Microsoft Windows, Linux, and Apple Mac OS X.

Some other examples of system software include:

BIOS: It stands for basic input output system. It is a type of system software, which is stored in Read Only Memory (ROM) located on the motherboard. However, in advanced computer systems, it is stored in flash memory. BIOS is the first software that gets activated when you turn on your computer system. It loads the drivers of the hard disk into memory as well as assists the operating system to load itself into the memory.
Boot Program: Boot refers to starting up a computer. When you switch on the computer, the commands in the ROM are executed automatically to load the boot program into memory and execute its instructions. The BIOS program has a basic set of commands that enables the computer to perform the basic input/output instructions to start the computer.
An assembler: It plays the role of a converter as it receives basic computer instructions and converts them into a pattern of bits. The processor uses these bits to perform basic operations.
A device driver: This system software controls hardware devices connected to a computer. It enables the computer to use the hardware by providing an appropriate interface. The kernel of a Computer's CPU communicates with different hardware through this software. Operating systems generally come with most of the device drivers. If the operating system does not have a device driver for hardware, you have to install the device driver before using that hardware device.

2) Application Software:

Application software is a set of programs designed to perform a specific task. It does not control the working of a computer as it is designed for end-users. A computer can run without application software. Application software can be easily installed or uninstalled as required. It can be a single program or a collection of small programs. Microsoft Office Suite, Adobe Photoshop, and any other software like payroll software or income tax software are application software. As we know, they are designed to perform specific tasks. Accordingly, they can be of different types such as:

Word Processing Software: This software allows users to create, edit, format, and manipulate the text and more. It offers lots of options for writing documents, creating images, and more. For example, MS Word, WordPad, Notepad, etc.
Spreadsheet Software: It is designed to perform calculations, store data, create charts, etc. It has rows and columns, and the data is entered in the cell, which is an intersection of a row and column, e.g., Microsoft Excel.
Multimedia Software: These software are developed to perform editing of video, audio, and text. It allows you to combine texts, videos, audio, and images. Thus, you can improve a text document by adding photos, animations, graphics, and charts through multimedia software. For example, VLC player, Window Media Player, etc.
Enterprise Software: These software are developed for business operational functions. It is used in large organizations where the quantum of business is too large. It can be used for accounting, billing, order processing and more. For example, CRM (Customer Relationship Management), BI (Business Intelligence), ERP (Enterprise Resource Planning), SCM (Supply Chain Management), customer support system, and more.

3) Programming Software:

It is a set or collection of tools that help developers in writing other software or programs. It assists them in creating, debugging, and maintaining software or programs or applications. We can say that these are facilitator software that helps translate programming language such as Java, C++, Python, etc., into machine language code. So, it is not used by end-users. For example, compilers, linkers, debuggers, interpreters, text editors, etc. This software is also called a programming tool or software development tool.

Some examples of programming software include:

Eclipse: It is a java language editor.
Coda: It is a programming language editor for Mac.
Notepad++: It is an open-source editor for windows.
Sublime text: It is a cross-platform code editor for Linux, Mac, and Windows.

Cloud Hosting

2021-07-04T19:53:00.001+05:30

Cloud Hosting

The method of outsourcing an enterprise's processing and storage capabilities to a service provider that provides its networking services in a utility model is cloud hosting.

The cloud vendor supervised the setup, cloud storage, protection and management, while customers will configure hardware and applications and scale servers online. Computing and storage services are dispersed in a cloud computing configuration through hundreds of virtual machines according to the load balance I / O demand.

Cloud Hosting

A cheaper alternative to the conventional dedicated server model that allows enterprises to develop and maintain their own data centers is the cloud storage model. Servers with dedicated hardware and virtual infrastructure exist on-premises throughout the conventional model, which can be an expensive operational cost for organizations.

Cloud hosting benefits

Cloud infrastructure provides companies with substantial financial and operating benefits, so they don't have to invest a lot in the actual direct cost of capital associated with data center acquisition and maintenance. IT also has the potential to scale more quickly, using only the services they need and paying for them. Moreover, long-term data storage becomes a more streamlined process, avoiding the expensive storage of discs and tape systems.

Data security advantages such as fast performance and disaster recovery are gained by utilizing cloud hosting services. Many companies use a hybrid model that combines on-site processing and storage capabilities with computation and storage in a cloud service framework.

Flexible and more cost-efficient scalability in developing apps, websites and other resources is one of the key advantages of using cloud computing services. As consumers are able to scale as needed, they are only paid for the facilities they use and do not pay for any unused facility. This payment system makes the cloud hosting a comparatively inexpensive storage process.

Although there are many advantages, it has some limitations also. Cloud protection challenges have attracted more interest as the pace of cloud adoption has increased. With data escaping the business data center, companies run the risk of fraud and degradation of intellectual property, violations of enforcement, lack of control into rogue workers' activities, and confidentiality breaches.

High supply, recovery point objective and recovery time objective (RTO) are additional factors to consider.

Top vendors/providers

As a technology model, cloud computing systems have fuelled a growth in the infrastructure under which a third-party vendor, usually with a pay-per-use system, provides a customer with the hardware, applications, servers, storage and networking facilities.

Amazon Web Services, the Google Cloud Portal, IBM Cloud and Microsoft Azure are common providers who offer cloud hosting. AWS, which provides comprehensive storage facilities and more areas and zones than most cloud vendors, is the leading competitor in the market. In recent years, Azure and Google have gained momentum.

AWS, along with Amazon Easy Storage Solution and Amazon Glacier for servers, provides the Elastic Compute Cloud to handle computing resources. For the enterprise, Google has the Google Compute Engine and Google Cloud Storage. Azure Virtual Machines and Azure Virtual Machine Scale Sets are supported by Microsoft Azure, and blob, log, and queue data are included in its data. A common cloud service is Microsoft Office 365.

Internet

2021-07-04T19:42:00.002+05:30

Internet

Internet is a global network that connects billions of computers across the world with each other and to the World Wide Web. It uses standard internet protocol suite (TCP/IP) to connect billions of computer users worldwide. It is set up by using cables such as optical fibers and other wireless and networking technologies. At present, internet is the fastest mean of sending or exchanging information and data between computers across the world.

It is believed that the internet was developed by "Defense Advanced Projects Agency" (DARPA) department of the United States. And, it was first connected in 1969.

Why is the Internet Called a Network?

Internet is called a network as it creates a network by connecting computers and servers across the world using routers, switches and telephone lines, and other communication devices and channels. So, it can be considered a global network of physical cables such as copper telephone wires, fiber optic cables, tv cables, etc. Furthermore, even wireless connections like 3G, 4G, or Wi-Fi make use of these cables to access the Internet.

Internet is different from the World Wide Web as the World Wide Web is a network of computers and servers created by connecting them through the internet. So, the internet is the backbone of the web as it provides the technical infrastructure to establish the WWW and acts as a medium to transmit information from one computer to another computer. It uses web browsers to display the information on the client, which it fetches from web servers.

The internet is not owned by a single person or organization entirely. It is a concept based on physical infrastructure that connects networks with other networks to create a global network of billions of computers. As of 12 August 2016, there were more than 300 crores of internet users across the world.

How does internet work?

Before understanding this let us understand some basics related to internet:

The internet works with the help of clients and servers. A device such as a laptop, which is connected to the internet is called a client, not a server as it is not directly connected to the internet. However, it is indirectly connected to the internet through an Internet Service Provider (ISP) and is identified by an IP address, which is a string of numbers. Just like you have an address for your home that uniquely identifies your home, an IP address acts as the shipping address of your device. The IP address is provided by your ISP, and you can see what IP address your ISP has given to your system.

A server is a large computer that stores websites. It also has an IP address. A place where a large number of servers are stored is called a data center. The server accepts requests send by the client through a browser over a network (internet) and responds accordingly.

To access the internet we need a domain name, which represents an IP address number, i.e., each IP address has been assigned a domain name. For example, youtube.com, facebook.com, paypal.com are used to represent the IP addresses. Domain names are created as it is difficult for a person to remember a long string of numbers. However, internet does not understand the domain name, it understands the IP address, so when you enter the domain name in the browser search bar, the internet has to get the IP addresses of this domain name from a huge phone book, which is known as DNS (Domain Name Server).

For example, if you have a person's name, you can find his phone number in a phone book by searching his name. The internet uses the DNS server in the same way to find the IP address of the domain name. DNS servers are managed by ISPs or similar organizations.

Now after understanding the basics, let us see how internet works?

When you turn on your computer and type a domain name in the browser search bar, your browser sends a request to the DNS server to get the corresponding IP address. After getting the IP address, the browser forwards the request to the respective server.

Once the server gets the request to provide information about a particular website, the data starts flowing. The data is transferred through the optical fiber cables in digital format or in the form of light pulses. As the servers are placed at distant places, the data may have to travel thousands of miles through optical fiber cable to reach your computer.

The optical fiber is connected to a router, which converts the light signals into electrical signals. These electrical signals are transmitted to your laptop using an Ethernet cable. Thus, you receive the desired information through the internet, which is actually a cable that connects you with the server.

Furthermore, if you are using wireless internet using wifi or mobile data, the signals from the optical cable are first sent to a cell tower and from where it reaches to your cell phone in the form of electromagnetic waves.

The internet is managed by ICANN (Internet Corporation for Assigned Names and Numbers) located in the USA. It manages IP addresses assignment, domain name registration, etc.

The data transfer is very fast on the internet. The moment you press enter you get the information from a server located thousands of miles away from you. The reason for this speed is that the data is sent in the binary form (0, 1), and these zeros and ones are divided into small pieces called packets, which can be sent at high speed.

Advantages of the Internet:

Instant Messaging: You can send messages or communicate to anyone using internet, such as email, voice chat, video conferencing, etc.
Get directions: Using GPS technology, you can get directions to almost every place in a city, country, etc. You can find restaurants, malls, or any other service near your location.
Online Shopping: It allows you to shop online such as you can be clothes, shoes, book movie tickets, railway tickets, flight tickets, and more.
Pay Bills: You can pay your bills online, such as electricity bills, gas bills, college fees, etc.
Online Banking: It allows you to use internet banking in which you can check your balance, receive or transfer money, get a statement, request cheque-book, etc.
Online Selling: You can sell your products or services online. It helps you reach more customers and thus increases your sales and profit.
Work from Home: In case you need to work from home, you can do it using a system with internet access. Today, many companies allow their employees to work from home.
Entertainment: You can listen to online music, watch videos or movies, play online games.
Cloud computing: It enables you to connect your computers and internet-enabled devices to cloud services such as cloud storage, cloud computing, etc.
Career building: You can search for jobs online on different job portals and send you CV through email if required.

Random Access Memory and its type

2021-05-25T20:51:00.004+05:30

What is RAM?

The full form of RAM is Random Access Memory. The information stored in this type of memory is lost when the power supply to the PC or laptop is switched off. The information stored in RAM can be checked with the help of BIOS. It is generally known as the main memory or temporary memory or cache memory or volatile memory of the computer system.

In this Operating system tutorial, you will learn:

What is RAM?
History of RAM
Types of RAM
SRAM VS DRAM

History of RAM

Here, are important landmarks from the history of RAM:

Type of RAM	Year Invented
FPM-(Fast page mode RAM)-	1990
EDO RAM (Extended data operations read-only memory)	1994
SDRAM (Single dynamic RAM)	1996
RDRAM (Rambus RAM)	1998
DDR (Double Data Rate)	2000
DDR2	2003
DDR3	2007
DDR4	2012

Types of RAM

Two main types of RAM are:

Static RAM
Dynamic RAM

Static RAM

Static RAM is the full form of SRAM. In this type of RAM, data is stored using the state of a six transistor memory cell. Static RAM is mostly used as a cache memory for the processor (CPU).

Dynamic RAM

DRAM stands for Dynamic Random Access Memory. It is a type of RAM which allows you to stores each bit of data in a separate capacitor within a specific integrated circuit. Dynamic RAM is a standard computer memory of the many modern desktop computers.

This type of RAM is a volatile memory that needs to be refreshed with voltage regularly. Else it loses the information stored on it.

SRAM VS DRAM

SRAM	DRAM
SRAM has lower access time, so it is faster compared to DRAM.	DRAM has higher access time, so it is slower than SRAM.
SRAM is costlier than DRAM.	DRAM costs less compared to SRAM.
SRAM requires a constant power supply, which means this type of memory which consumes more power.	DRAM offers reduced power consumption because the information is stored in the capacitor.
It is a complex internal circuitry, and it offers less storage capacity is available compared to the same physical size of a DRAM memory chip.	It is the small internal circuitry in the one-bit memory cell of DRAM. The large storage capacity is available.
SRAM has a low packaging density.	DRAM has a high packaging density.