ग्लोस्सरी Computer

Application :
An application, or application program, is a software program that runs on your computer. Web browsers, e-mail programs, word processors, games, and utilities are all applications. The word "application" is used because each program has a specific application for the user. For example, a word processor can help a student create a research paper, while a video game can prevent that same student from getting the paper done.

In contrast, system software consists of programs that run in the background, enabling applications to run. These programs include assemblers, compilers, file management tools, and the operating system itself. Applications are said to run on top of the system software, since the system software is made of of "low-level" programs. While system software is automatically installed with the operating system, you can choose which applications you want to install and run on your computer.

Bandwidth :
Bandwidth refers to how much data you can send through a network or modem connection. It is usually measured in bits per second, or "bps." You can think of bandwidth as a highway with cars travelling on it. The highway is the network connection and the cars are the data. The wider the highway, the more cars can travel on it at one time. Therefore more cars can get to their destinations faster. The same principle applies to computer data -- the more bandwidth, the more information that can be transferred within a given amount of time.

CD-ROM :
Stands for "Compact Disc Read-Only Memory." A CD-ROM is a CD that can be read by a computer with an optical drive. The "ROM" part of the term means the data on the disc is "read-only," or cannot altered or erased. Because of this feature and their large capacity, CD-ROMs are a great media format for retail software. The first CD-ROMs could hold about 600 MB of data, but now they can hold up to 700 MB. CD-ROMs share the same technology as audio CDs, but they are formatted differently, allowing them to store many types of data.

Debug:
Computer programmers, like everybody else, are not perfect. This means the programs they write sometimes have small errors, called "bugs," in them. These bugs can be minor, such as not recognizing user input, or more serious, such as a memory leak that crashes the program. Before releasing their software to the public, programmers "debug" their programs, eliminating as many errors as possible. This debugging process often takes a long time, as fixing some errors may introduce others. Debugging your windshield at a gas station is much easier than debugging a computer program.

E-commerce :
E-commerce (electronic-commerce) refers to business over the Internet. Web sites such as Amazon.com, Buy.com, and eBay are all e-commerce sites. The two major forms of e-commerce are Business-to-Consumer (B2C) and Business-to-Business (B2B). While companies like Amazon.com cater mostly to consumers, other companies provide goods and services exclusively to other businesses. The terms "e-business" and "e-tailing" are often used synonymously with e-commerce. They refer to the same idea; they are just used to confuse people trying to learn computer terms.

Firewall :
The term "firewall" originally referred to fireproof walls that were designed to prevent the spread of fire from one room or building to the next. They were typically made of brick, steel, or another type of inflammable material that would effectively limit the spread of the fire. In the IT world, firewalls do not involve any fire or pyrotechnics, but they serve a similar purpose. A computer firewall limits the data that can pass through it and protects a networked server or client machine from damage by unauthorized users.

Firewalls can be either hardware or software-based. A router is a good example of a hardware device that has a built-in firewall. Most routers can be configured to limit traffic from certain IP addresses or block requests based on other criteria. Software programs that monitor and restrict external access to a computer or network can also serve as firewalls. A network firewall only allows authorized traffic from the Internet to flow in and out of the network.

Gigabyte :
A gigabyte is 2 to the 30th power, or 1,073,741,824 bytes.

It can be estimated as 10 to the 9th power, or one billion (1,000,000,000) bytes. A gigabyte is 1,024 megabytes and precedes the terabyte unit of measurement. Hard drive sizes are typically measured in gigabytes, such as a 160GB or 250GB drive. The term gigabyte is often often abbreviated as simply a "gig" in speech. For example, if you have a 250GB hard drive, you could say, "I have 250 gigs of disk space." The prefix "giga" comes from the Greek word "gigas," meaning giant.

For a list of all the different units of measurements, view this Help Center article.
Abbreviation: GB

Hacker :
While this term originally referred to a clever or expert programmer, it is now more commonly used to refer to someone who can gain unauthorized access to other computers. A hacker can "hack" his or her way through the security levels of a computer system or network. This can be as simple as figuring out somebody else's password or as complex as writing a custom program to break another computer's security software. Hackers are the reason software manufacturers release periodic "security updates" to their programs. While it is unlikely that the average person will get "hacked," some large businesses and organizations receive multiple hacking attempts a day.

Hardware :
Computer hardware refers to the physical parts of a computer and related devices. Internal hardware devices include motherboards, hard drives, and RAM. External hardware devices include monitors, keyboards, mice, printers, and scanners.

The internal hardware parts of a computer are often referred to as components, while external hardware devices are usually called peripherals. Together, they all fall under the category of computer hardware. Software, on the other hand, consists of the programs and applications that run on computers. Because software runs on computer hardware, software programs often have system requirements that list the minimum hardware required for the software to run.

HDTV :
Stands for "High Definition Televsion." HDTV is a high-quality video standard developed to replace older video formats often referred to as SDTV (standard definition television). While HDTV's video quality is one of the most noticeable improvements over SDTV, HDTV includes a number of other important improvements as well.

First of all, the HDTV signal is digital. Instead of an analog signal, used by traditional NTSC broadcasts, HDTV is always digital. This eliminates analog interference caused be electrical currents and magnetic fields. Secondly, HDTV uses a different aspect ratio than SDTV. While previous broadcasts used a 4:3 ratio (4 units wide for every 3 units tall), HDTV uses a ratio of 16:9. This wider aspect ratio more closely emulates how humans see the world, making the image appear more realistic. This ratio is also better for watching widescreen movies, which are recorded in widescreen for the same reason.

True to its name, high definition television offers a much higher resolution than standard definition video. While a typical analog broadcast in the U.S. contains a maximum of 525 horizontal lines of resolution, an HDTV signal supports up to 1080. The three formats used by HDTV are 1080i (interlaced), and 720p and 1080p (progressive). HDTV's higher resolution produces images that are much finer and contain more detail and more color than previous formats. HDTV also provides a higher-quality digital audio signal than SDTV and supports up to six audio channels compared to the two channels allowed previously.

To watch HDTV, you need an HDTV-compatible television and a means of receiving an HDTV signal. HDTVs come in both 16:9 and 4:3 formats (for backwards compatibility). Some HDTVs include HDTV tuners for receiving over-the-air broadcasts, but others require the receiver to be bought separately. Fortunately, most cable and satellite TV companies offer HDTV-compatible boxes with their digital service plans.

IMAP :
Stands for "Internet Message Access Protocol" and is pronounced "eye-map." It is a method of accessing e-mail messages on a server without having to download them to your local hard drive. This is the main difference between IMAP and another popular e-mail protocol called "POP3." POP3 requires users to download messages to their hard drive before reading them. The advantage of using an IMAP mail server is that users can check their mail from multiple computers and always see the same messages. This is because the messages stay on the server until the user chooses to download them to his or her local drive. Most webmail systems are IMAP based, which allows people to access to both their sent and received messages no matter what computer they use to check their mail.

Most e-mail client programs such as Microsoft Outlook and Mac OS X Mail allow you to specify what kind of protocol your mail server uses. If you use your ISP's mail service, you should check with them to find out if their mail server uses IMAP or POP3 mail. If you enter the wrong protocol setting, your e-mail program will not be able to send or receive mail. For more information about IMAP, check out the IMAP Connection.

Java :
While most of the world uses "Java" as another term for coffee, the computer science world uses it to refer to a programming language developed by Sun Microsystems. The syntax of Java is much like that of C/C++, but it is object-oriented and structured around "classes" instead of functions. Java can also be used for programming applets -- small programs that can be embedded in Web sites. The language is becoming increasingly popular among both Web and software developers since it is efficient and easy-to-use.

Java is a great programming language, but like Reading Rainbow says, you don't have to take my word for it. Sun Micorsystems describes Java as a "simple, object-oriented, distributed, interpreted, robust, secure, architecture-neutral, portable, high-performance, multithreaded, dynamic, buzzword-compliant, general-purpose programming language." And it removes stains like magic.

JavaScript :
Like Java, this is a programming lanuguage designed by Sun Microsystems, in conjuction with Netscape, that can be integrated into standard HTML pages. While JavaScript is based on the Java syntax, it is a scripting language, and therefore cannot be used to create stand-alone programs. Instead, it is used mainly to create dynamic, interactive Web pages. For example, Web developers can use JavaScript to validate form input, create image rollovers, and to open those annoying pop-up windows. Like so many other things, we have to take the good with the bad.

Joystick :
A joystick is an input device commonly used to control video games. Joysticks consist of a base and a stick that can be moved in any direction. The stick can be moved slowly or quickly and in different amounts. Some joysticks have sticks that can also be rotated to the left or right. Because of the flexible movements a joystick allows, it can provide much greater control than the keys on a keyboard.

Joysticks typically include several buttons as well. Most joysticks have at least one button on the top of the stick and another button in the front of the stick for the trigger. Many joysticks also include other buttons on the base that can be pressed using the hand that is not guiding the stick. Joysticks typically connect to your computer using a basic USB or serial port connection and often come with software that allows you to assign the function of each button.

Since joysticks emulate the controls of planes and other aircraft, they are best suited for flight simulators and flying action games. However, some gamers like to use joysticks for other types of video games, such as first-person shooters and fighting games. Others prefer using the basic keyboard and mouse, with which they are already accustomed to.