A Glossary of Computer Terms

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Apple Computer: One of the leading computer manufacturers in the U.S., Apple computer is noted primarily for developing the Macintosh line of computers. Apple computer is also noted for gettin g a strong foothold in the education market with special discounts for schools and students. As a result, many schools use Macintosh or the older Apple II computers almost exclusively.

Application: Also known as a program, an application is a piece of software that makes the computer perform a specific task. For instance, a word processor can be used to write a le tter or report, while a drawing program can be used to make pictures on a computer.

Baud: Also known as bps, a baud is a measure of how fast a modem can transmit information. One baud is equal to one bit per second. Most modern modems transmit at rates of 14,400 baud.

Bit: Short for Binary Digit, this is the smallest unit of information a computer deals with. A bit is either a 1 or a 0. By stringing bits together, computers can represent any kind of information that we want them to.

Boolean Expression: Any expression that evaluates to either "true" or "false". The basic operations in boolean expressions are AND, OR, and NOT (sometimes represented as ^,+, and ! respectively).
T AND T = T
T AND F = F
F AND T = F
F AND F = F

T OR T = T
T OR F = T
F OR T = T
F OR F = F

NOT T = F
NOT F = T

Byte: A string of 8 bits, such as "10010110". A byte is the basic unit of information typically used by a computer.
See also:Kilobyte, Megabyte,Gigabyte, Terabyte.

Chooser: This is the Macintosh desk accessory (DA) that is used to connect 2 nodes on a network (i.e. 2 computers, or a computer and a printer).

Clone: This is a computer made with chips licenced from another manufacturer, thus making a compatible machine. IBM clones have been out since the early 1980's, but Macintosh clones have appeared only in the last year. By letting other manufacturers use their chips, IBM greatly expanded the variety and number of computers compatible with their own.

CompuServe: Another commercial service for people with a modem. It is similar to America On Line, but geared toward more experienced users.

FAQs: Acronym for Frequently Asked Questions. Almost everything on the Internet has a FAQ section for new users.

Floppy Disk: A flimsy plastic disk with a magnetic coating for storing information permanently on a computer. Most floppies today are 3.5 inches in diameter and store about 1.4 megabytes.

GIF: Acronym for Graphics Interchange Format. GIF is one of the two primary formats for graphics on the world wide web (the other being jpeg.) GIF is distinguished by its limitation of 256 colors in an image and its usefulness in compressing images with large areas of flat color. A second format of GIF (sometimes referred to as GIF89a) allows for a limited form of animation in an image. Most animations in web pages these days are animated GIFs.

Gigabyte: Abbreviated as GB or gig, this is a unit of information equal to 2^30 bytes (1,099,511,627,776 bytes), or 2^20 kilobytes (1,048,576 kilobytes), or 2^10 megabytes (1,024 megabytes). Many hard drives these days have between 1 and 2 gigabytes of storage space.

Hard Disk: A quickly spinning platter (usually made of aluminum) with a magnetic coating, used to store large amounts of information permanently on a computer. As opposed to a floppy disk, which operates on roughly similar principles but is slower, cheaper, and stores much less information than a hard disk.

Hardware: This is all the "physical" components of a computer. Hardware includes the monitor (screen), the CPU, the keyboard, and most other computer equipment. This is opposed to software, which is the files and programs that make the computer work. One programmer has defined hardware as "The part of a computer that can be kicked."

Hex, Hexidecimal: Also known as base 16, this is a number system which has 16 digits: the normal 10 (0, 1, 2, 3, 4, 5, 6, 7, 8, and 9), and 6 extras (A, B, C, D, E, and F)."A" In hex equals "10" in decimal, "B" in hex equals "11" in decimal, and so on up to F=15. Hex is widely used by programmers because a single hex digit can be used to exactly represent 4 bits, and so 2 hexidecimal digits can be used to exactly represent a byte. The normal decimal system does not coincide nearly so well with the binary system used by computers.

Home Page: This is a name for the page that comes up by default when someone starts up their web browser. Often used as the "starting point" to a web site.

HTML: Acronym for HyperText Markup Language, the format used by the world wide web for encoding web pages. HTML uses a series of tags to allow web designers to define how a page looks. A web browser translates the HTML into what you see on the screen. You can see the HTML behind a web page by using the "View Source" command on your web browser. HTML specifications have been upgraded from time to time, making new features available to web desingers and viewers. Sometimes a browser will provide support for a tag not supported by the general HTML standard, making some pages look bad in other browsers. Netscape is somewhat notorious for doing this.

IBM: International Buisness Machines (IBM) is one of the world's major computer manufacturers and was the primary influence in personal computing in the early 1980s. By licencing clones, IBM gained a strong foothold in the personal computer buisness. IBM now primarily manufactures mainframes.

Internet: The large, worldwide network that allows for functions such as email, the world wide web (WWW), and many other things. The internet provides the framework for all these services to run on.

JPEG: Acronym for Joint Photograpics Experts Group, which invented it. JPEG is one of the two most popular formats for graphics on the world wide web (the other being GIF). JPEG is distinguished by its ability to use up to 16 million colors in an image and its usefullness in compressing photographic images.

Kilobyte: Abbreviated as KB or K, this is a unit of information equal to 2^10 bytes (1,024 bytes). A page of plain text represents about 3 kilobytes of information.

Mac, Macintosh: A type of personal computer, noted for being the first to use a graphical user interface, as well as being a favorite computer of graphic artists.

Mainframe: A large, expensive computer, often used as a server for a large company or institution.

Megabyte: Abbreviated as MB or meg, this is a unit of information equal to 2^20 bytes (1,048,576 bytes), or 2^10 kilobytes (1,024 kilobytes). Most computers these days hav e anywhere from 4 to 16 or more megabytes of RAM.

Menu: A collection of related commands (called menu items) for an application. A menu typically stays in the menu bar, where it is represe nted as a single word until the user selects it. There are other kinds of menus, called popup menus, to which this does not apply.

Menu Bar: Where menus are found, usually in a horizontal bar across the top of the screen.

Menu Item: A single command in a menu, which remains hidden until the user selects the menu to choose a command from.

Modem: A device for connecting a computer to a telephone line. A modem translate information from a computer into signals on a phone line, and vice-versa. Modems make economical communication between distant com puters practical. Although other technologies are trying to replace modems in this function, it will likely be several years before that happens.

Netscape: The company that makes Netscape Navigator, which is currently the most popular web browser on the market. Navigator supports many nonstandard extensions to web pages. Pages th at support these extensions are called Netscape Enhanced.

Netscape Enhanced: A term for identifying web pages that use the nonstandard enhancements supported by Netscape Navigator. While such pages do look better with the enhancements to someone using Navigator, the y often don't look too good when viewed by other web browsers.

Network: A group of computers that are connected in order to share information or expensive hardware such as printers and hard disks.

Newbie: Someone who is new to computers, the internet, or a particular service on the internet. Often used to indicate someone who needs some coaching to be able to do what they're trying to do right. Also used as a derogatory term for people who make stupid mistakes online.

Newline (new line) character: Is the character that you type by hitting the "Return" key on the keyboard. It is generally used to end a line of text and begin a new one.

Operating System: The software that controls how a computer and a human interact with each other. The major operating systems in use today include: DOS, Macintosh, Windows, Windows '95, and UNIX.

RAM/ROM: These are 2 kinds of memory in a computer. RAM (Random Access Memory) is the kind of memory that gets erased when the computer is turned off. This is also where the programs that you are running get stored while you are using them. ROM (Read Only Memory) does not get erased when the computer is turned off. ROM is used for storing the instuctions that a computer cannot do without or that programmers need to use frequently. ROM is sometimes referred to as firmware.

Search Engine: A program that searches through a database and returns records matching specified criteria to the user. Although they have been used in one form or another since the 1970's (and perhaps even before), they have become most famed lately for being used on the internet. Yahoo, Lycos, and Altavista are just a few examples of search engines that return web pages matching user specified keywords.

Server: A central computer on a network that is used by other computers or terminals. The server on a network is usually used to store information that needs to be frequently updated and accessed from different locations.

Software: This includes all the programs and files that make computers work. Any program, no matter where it is stored, is considered software. This is opposed to hardware, which is the actual "physical" computer equipment (and basically includes everything that is not software).

Terminal: Essentially just a screen and keyboard connected to a server. Terminals are often used for access to large databases on a server (such as a library's card catalog).

Terabyte: Only sometimes abbreviated as TB, this is a unit of information equal to 2^30 kilobytes (1,099,511,627,776 kilobytes), or 2^20 megabytes (1,048,576 megabytes), or 2^10 gigabytes (1,024 gigabytes). This is so large as to be rarely used in general.

UNIX: An old but still very useful operating system, this is the dominant operating system for web servers.

Web Browser: An application used to use the World Wide Web. It is the job of the browser to transform the instructions in a web page into what you see on the screen.

Web Page: A single "spot" on the World Wide Web. Pages are the units from which web sites are built. This glossary is a single page on the EPAL Web Site.

Web Site: A (usually) cohesive set of web pages set up and maintained by a single individual or organization. Pages on good web sites generally look similar to each other.

World Wide Web: A graphically based way of exchanging information on the internet. The world wide web is made up of servers containing web sites made up of web pages.