it's IT

SPAM

2010-12-07T14:55:00.003+07:00

Spam

Spam is an unsolicited e-mail message or newsgroup posting sent to many recipients or newsgroup at once. Spam is Internet junk mail. The content of spam ranges from selling a product or service, to promoting a business opportunity, to advertising offensive material. Once study indicates more than 80 percent of e-mail is spam. Instead of via e-mail, some spam is sent through an instant messaging system and, thus, is called spim. Another type, called spit, is spam sent via VoIP.

Users can reduce the amount of spam they receive with a number of techniques. Some e-mail programs have built-in settings that allow users to delete spam automatically. Users also can sign up for e-mail filtering from their Internet access provider. E-mail filtering is a service that blocks e-mail messages from designated sources. These services typically collect the anytime. An alternative to e-mail filtering is to purchase an anti-spam program that attempts to remove spam before it reaches your inbox. The disadvantages of e-mail filter and anti-spam programs is that sometimes they remove valid e-mail messages. Thus, users should review the contents of the spam messages periodically to ensure they do not contain valid messages.

Companies of the Cutting Edge

2010-11-30T23:40:00.004+07:00

AMAZON

Online shoppers can find practically any product they desire on Amazon.com. Billing itself as the “Earth’s most customer-centric company,” it offers books, movies, electronics, clothing, toys, and many other items.

Jeff Bezos founded Amazon in 1995 knowing that book lovers would gravitate toward a web site offering the convenience of browsing through millions of book titles in one sitting. He fulfilled orders for customers in every U.S. state and 45 additional countries during the first 30 days of business. All shipped from his Seattle-area garage.

The company has grown to permit third parties to sell product on its Web site. Its kindle portable reader wirelessly downloads more than 135,000 books along with blogs, magazines, and newspapers to a high-resolution electronic paper display. In 2008, it launched TextBuyIt. Which lets customers use text messages to buy products sold on Amazon.com.

eBAY

Millions of product are traded daily on eBay auctions, whether it is across town or across the globe. The more then 62 million registered worldwide shoppers generate at least $ 1.5 billion on the main Web site, eBay, along with items on shopping.com, tickets on StubHub, classified on Kijiji, and other e-commerce venues.

The shoppers likely pay for their merchandise using PayPal, another eBay service. This merchant service allows buyers to transfer money from savings accounts or use their credit card without having to expose the account number to the seller. Skype, an eBay service, allows moe than 340 millions registered Internet users to make video and voice calls worldwide. Other eBay companies are Rent.com, which allows consumers to find and compare product. In 2008, eBay introduce major initiatives to protect its bidders from fraudulent offers and malicious content.

Photo Editing and Photo Management Software

2010-11-30T23:31:00.003+07:00

photo editing software

Instead of professional photos editing software, many home and small business users work with easier-to-use personal photo editing software, which is available both as packaged software and as web applications. Personal photo editing software allows users to edit digital photos by removing red-eye, erasing blemishes, restoring aged photos, adding special effects, enhancing image quality, or creating electronic photo albums. When you purchase a digital camera, it usually includes photo editing software. Some digital cameras even basic photo editing software built in so that you can edit the image directly on the camera. You can print edited photos on labels, calendars, business cards, and banners, or post them on the Web . Some photo editing software allows users to send digital photos to an online print service, which will deliver high-resolution printed images through the postal service or allow you to pick them up at a local store. Many online print services also have a photo community where users can post photos on the Web for other to view and purchase, if desired.

With photo management software, you can view, organize, sort, catalog, print, and share digital photos. Some photo editing software includes photo management functionality.

Pointing Devices

2010-11-28T11:30:00.003+07:00

The mouse is the most widely used pointing devices today. Some users, however, work with other pointing devices. These include the trackball, touchpad, pointing stick, touch screen, touch-sensitive pads, stylus, pen, signature capture pad, and graphic tablet. But in this article I just want to explain you about Trackball, Touchpad, and Pointing stick.

Trackball

Trackball

A Trackball is a stationary pointing device with a ball on its top or side. The ball in most trackballs is about the size of a Ping-Pong ball.

To move the pointer using a trackball, you rotate the ball with your thumb, fingers, or the palm of your hand. I addition to the ball, a trackball usually has one or more buttons that work just like mouse buttons.

A trackball requires frequent cleaning because it picks up oils from fingers and dust from the environment. For users who have limited desk space, however, a trackball is a good alternative to a mouse because the device is stationary.

Touchpad

Touchpad

A touchpad is a small, flat, rectangular pointing device that is sensitive to pressure and motion. To move the pointer using a touchpad, slide your fingertip across the surface of the pad. Some touchpad have or more buttons around the edge of the pad that work like mouse buttons. On most touchpads, you also can tap the pad’s surface to imitate mouse operations such as clicking. Touchpads are found most often in notebook computers.

Pointing Stick

A pointing Stick is a pressure-sensitive pointing device shape like a pencil eraser that is positioned between keys on a keyboard. To move the pointer using a pointing stick, you push the pointing stick with a finger. The pointer on the screen moves n the direction you push the pointing stick. By pressing buttons below the keyboard, users can click and perform other perform other mouse-type operations with a pointing stick. A pointing stick does not require any additional desk space.

System Software

2010-11-23T15:20:00.004+07:00

System Software consists of the programs that control or maintain the operations of the computer and its devices. System software serves as the interface between the user, the application software, and the computer’s hardware. Two types of system software are the operating system and utility programs.

Window 7

An Operating System is a set of programs that coordinates all the activities among computer hardware devices. It provides a means for users to communicate with the computer and other software. Many of today’s computers use Microsoft’s Windows or Mac OS, Apple’s Operating system.

When a user starts a computer, portions of the operating system are copied into memory from the computer’s hard disk. These parts of the operating system remain in memory while the computer is on.

A Utility Program allows a users to perform maintenance-type tasks usually related to managing a computer, its devices, or its programs. For example, you can use a utility program to transfer digital photos to an optical disc. Most operating system include several utility programs for managing disk drivers, printers, and other devices and media. You also can buy utility programs that allow you to perform additional computer management functions.

HTML and XHTML

2010-11-23T15:18:00.003+07:00

HTML (Hypertext Markup Language) is a special formatting language that programmers use to format document for display on the Web. You view a Web page written with HTML in a Web browser such as Internet Explorer, Safari, Firefox, Opera, or Google Chrome. Similarly, XHTML (extensible HTML) is a markup language that enables Web sites to be displayed more easily on microbrowsers in smart phones and other mobile devices, as well as on desktop and notebook computers.

HTML and XHTML are not actually programming languages. They are however, languages that have specific rules for defining the placement and format of text, graphics, video, and audio on a Web page. HTML and XHTML use tags or element, which are words, abbreviations, and symbols that specify links to other document and indicate how a Web page is displayed when viewed on the Web.

A Web page, thus, is a file that contains both text and HTML and/or XHTML tags. Examples of tags are <p> to indicate a new paragraph, <tr> to create a new row in a table, and <title> to define a document title. You can write HTML code using any text editor such as Notepad. Many programmers however, never write HTML and XHTML code because several programming languages and program development tools generate it automatically

Wi-Fi

2010-11-11T08:19:00.005+07:00

Computers and devices that have the appropriate wireless capability can communicate via radio waves with other computers or devices using Wi-Fi (wireless fidelity), which identifies any network based on the 802.11 standards. Developed by IEEE, 802.11 is a series of network standards that specifies how two wireless devices communicate over the air with each other. A designation of 802.11 a/b/g on a computer or device indicate it supports all three standards. The newest standard, 802.11n, uses multiple transmitters and receivers, known as MIMO (multiple-input multiple-output), to reach speeds from 2 to 10 times faster than 802.11g.

Wi-Fi sometimes is referred to as wireless Ethernet because it uses techniques similar to the Ethernet standard to specify how physically to configure a wireless network. Thus, Wi-Fi network easily can be integrated with wired Ethernet networks. When a Wi-Fi network accesses the Internet, it works in conjunction with the TCP/IP network standard.

Wi-Fi Certified products are guaranteed to be able to communicate with each other. Most of today’s computers and many mobile devices, such as smart phones and handheld game consoles, are Wi-Fi enabled.

One popular use of the Wi-Fi network standard is in hot spot that offer mobiles users the ability to connect to the Internet with their Wi-Fi enabled wireless computers and devices. Many homes and small businesses also use Wi-Fi to network computers and devices wirelessly. In open or outdoor areas free from interferences, the computers or devices should be within 300 feet of each other. In closed areas, the wireless network range is about 100 feet. To obtain communications of the maximum distances, you may need to install extra hardware.

Some large areas, such as college or business campuses, are set up as a Wi-Fi mesh network, in which each mesh node routes its data to the next available node until the reaches its destination usually an Internet connection. A Wi-Fi mesh network is more flexible than a hot spot because each node in a mesh network does not have to directly connected to the Internet.

Mobile Computers and Mobile Devices

2010-11-08T09:39:00.002+07:00

A mobile computer is a personal computer you can carry from place to place. Similarly, a mobile device is a computing device small enough to hold in your hand.. the most popular type of mobile computer is the notebook computer. The following sections discuss the notebook computer and widely used mobile devices.

Notebook Computers

notebook

A notebook computer, also called a laptop computer, is a portable, personal computer designed to fit on your lap. Notebook computers are thin and lightweight, yet they can be as powerful as the average desktop computers usually are more expensive then desktop computers with equal capabilities.

On a typical notebook computer, the keyboard is on top of the system unit, and the monitor attaches to the system unit with hinges. These computers weigh on average from 2.5 to more 10 pounds (depending on configuration), which allows users to transport the computers can operate on batteries or a power supply or both.

Mobile Devices

Mobile Devices, which are small enough to carry in a pocket, usually do not have disk drivers. Instead, these devices store programs and data permanently on special memory inside the system unit or on small storage media such as memory cards. You often can connect a mobile devices to a personal computer to exchange information between the computer and the mobile devices.

Some mobile devices are Internet-enabled, meaning they can connect to the Internet wirelessly. With an Internet-enabled devices, users can chat, send e-mail and instant messages, and acces the web. Because of their reduced size, the screens on mobile devices are small, but usually are in color.

Five popular types of mobile devices are smart phones. PDAs, handheld computers, portable media players, and digital cameras.

UNIX and Linux

2010-11-03T09:39:00.002+07:00

UNIX

UNIX (pronounced YOU-nix) is a multitasking operating system developed in the early 1970s by scientists at Bell Laboratories. Bell Labs (a subsidiary of AT&T) was prohibited from actively promoting UNIX in the commercial marketplace because of federal regulations. Bell Labs instead licensed UNIX for a low fee to numerous college and universities, where UNIX obtained a wide following. UNIX was implemented on many different types of computers. After deregulation of telephone companies in the 1980s, UNIX was licensed to many hardware and software companies.

Several versions of this operating system exist, each slightly different. When programmers move application software from one UNIX version to another, they sometimes have to rewrite some of the program. Although some versions of UNIX have a command-line interface, most versions of UNIX offer a graphical user interface.

Today, a versions of UNIX is available for most computers of all sizes. Power users often work with UNIX because of its flexibility and power. Manufacturers such as Sun and IBM sell personal computers and workstation with a UNIX operating system.

Linux

Linux Ubuntu

Linux is one of the faster growing operating system. Linux (pronounced LINN-uks), introduced in 1991, is a popular multitasking UNIX-type operating system. In addition to the basic operating system, Linux also include many programming languages and utility programs.

Linux is not proprietary software like the operating system discussed thus far. Instead, Linux is open source software, which means its code is provide for use, modification, and redistribution. It has no restrictions from copyright holder regarding modification of the software. Many programmers have donated time to modify and redistribute Linux to make it the best possible version of UNIX. Promoters of open source software state two main advantage: users who modify the software share their improvements with others, and costumers can personalize the software to meet their needs.

Linux is available in variety of forms, known as distributions. Some distributions of Linux are command-line. Other are GUI. The two most popular GUIs available for Linux are GNOME and KDE. Some companies such as Red Hat market software that runs on their own distribution of Linux. Many application program, utilities, and plug-ins have Linux distributions, including OpenOffice.org, StarOffice, Mozilla, Netscape, Yahoo! Messenger, RealPlayer, QuickTime, and Acrobat Reader.

Users obtained Linux in a variety of ways. Some download it free from the Web. Other purchase it from vendors such as Red Hat or IBM, who bundle their own software with the operating system. Linux optical discs are included in many Linux books and also are available for purchase from vendors. Some retailers such as Dell will preinstall Linux on a new computer’s hard disk on request. If you want to preview the Linux operating system, you can obtain a Live CD or Live USB.

Computer viruses, worms, trojan horses, and rootkit

2010-10-22T11:17:00.001+07:00

· A computer virus is a potentially damaging computer program that affects, or infects, a computer negatively by altering the way the computer works without the user’s knowledge or permission. Once the virus infects the computer, it can spread throughout and may damage files and system software, including the operating system.

· A worm is a program that copies itself repeatedly, for example in memory or on a network, using up resources and possibly shutting down the computer or network.

· A Trojan horses (named after the Greek myth) is a program that hides within or looks like a legitimate program. A certain condition or action usually triggers the Trojan horse. Unlike a virus or worm, a Trojan horse doesn’t replicate itself to other computers.

· A rootkit is a program that hides in a computer and allows someone from a remote location to take full control of the computer. Once the rootkit is installed, the rootkit author can execute programs, change settings, monitor activity, and access files on the remote computer. Although rootkits can have legitimates uses, such as in law enforcement, their use in nefarious and illegal activities is growing rapidly.

Computer viruses, worms, Trojan horse, and rootkits are classified as a malware (shortcut for malicious software), which are programs that act without a user’s knowledge and deliberately alter the computer’s operations. Other classes of malware include back doors and spyware. Although malware often falls in one of these classes (virus, worm, Trojan horse, rootkit, back door, or spyware), some malware has characteristic of two or more classes. For example. MyDoom and blaster are worms; Melissa has element of a virus, worm, and Trojan horse.

Unscrupulous programmers write malware and then test it to ensure it can deliver its payload. The payload is the destructive event or prank the program is intended to deliver. A computer infected by a virus, worm, Trojan horse, or rootkit often has one or more of the following symptoms:

· Operating system runs much slower than usual

· Available memory is less than expected

· Files become corrupted

· Screen displays unusual message or image

· Music or unusual sound plays randomly

· Existing programs and files disappear

· Programs or files do not work properly

· Unknown programs or files mysteriously appear

· System properties change

· Operating system doesn’t start up

· Operating system shuts down unexpectedly

Malware delivers its payload on a computer in a variety of ways: when a user open an infected file,runs infected program, boots the computer with infected removable media inserted in a drive or plugged in a port, connects an unprotected computer to a network, or when certain condition or event occurs, such as the computer’s clock changing to a specific date. Today, a common way computers become infected with viruses and other malware is through users opening infected e-mail attachments.

Currently, more than 180,000 known viruses, worms, Trojan horse, rootkit and other malware exist. Many web sites maintain lists of all known malware.