Glossary of Computer Terms
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Active WindowThe window that is currently selected.
Application Software that is used for a particular task, such as word processing or database management. This term is used interchangeably with the word program.
Back Up (verb) To make a copy of programs or data files to prevent accidental loss. You back up all of your work on a removable disk in case the main copy is deleted or damaged. You can restore the main copy from the back up copy.
(noun) A copy of a program or data file.
Binary See bit.
Bit Short for binary digit (either a 1 or 0 in the binary number system). A bit is the smallest unit of information processed by a computer. There are 8 bits in a byte.
Bitmap A file format for digital images that can be processed by Windows programs.
Browser An application to find, read, and print information from the World Wide Web.
Button A graphic element (icon) resembling a push button that, when clicked, performs a specified command. Also refers to mechanical buttons on the mouse.
Byte A unit of information (8 bits) that represents a single character such as a letter or a number. Because bytes are so small, computer memory and disk storage amounts are usually given in kilobytes (KB, one thousand bytes), megabytes (MB, one million bytes), or gigabytes (GB, one billion bytes).
CD or CD-ROM Compact Disc-Read Only Memory contains up to 650 million bytes of text, video and sound information. You cannot make changes to the disc.
CD-R A compact disc (CD) to which you can write data once; the data cannot be changed after it is written. Writing to a CD-R or CD-RW requires a CD disk drive designed for reading and writing. Many CD drives will only read, not write, CDs.
CD-RW Compact Disc-Read Write CDs can be used to copy and store data or other types of files. Changes can be made to these discs. They are more expensive and less reliable than CD-R discs. See CD-R.
Character Any letter, number, or symbol such as a punctuation mark. Computers are very literal. They will read each character, including letters, punctuation and even the spaces between them.
Check Box A small square in a dialog box that adds or removes a check mark when it is clicked. Each check box represents an option or choice. Any, none, or all check boxes in a category may be selected at a time. Also see Radio Button.
Clipboard A temporary storage location used to transfer data between documents and between applications. Typically, you transfer data to the clipboard by using an application’s Copy or Cut command and you insert data from the clipboard by using the application’s Paste command.
CPU/Processor The Central Processing Unit, often called the microprocessor or system unit, is the computational and control unit of the computer.
Cursor The vertical line that marks where information will be entered when typing text or pasting from the clipboard.
Default The method by which an action is taken automatically, unless a different method is set by the user. The operating system and applications come with defaults set by the manufacturer, and the user can set different defaults.
Desktop The main screen where windows, icons, menus, and dialog boxes appear.
Dialog Box A small window displayed by the operating system or a program. It contains options (such as command buttons, check boxes, radio buttons, list boxes, etc.) that the user may select.
Digital Image An image (picture or graphic) that is in binary format so that it can be processed by a computer.
Disk A medium for storing information. It can be a hard drive in the computer, or a removable disk such as a floppy disk, external USB drive, CD or DVD, or even memory in an attached camera. (When referring to CDs and DVDs, the spelling is disc.)
Document Information or Data that is created using an application. A document may be a business report, a spreadsheet, a picture, a letter, or other format. It can be printed, but is stored in a computer as a file.
Drive or Disk Drive A device used for storing and retrieving information on disks.
Driver A program that tells the operating system how to interact with the computer’s hardware.
DVD A Digital Video Disc or Digital Versatile Disc. A DVD is similar to a CD but with much greater capacity (4.5 GB). See CD, CD-R, CD-RW.
email (verb) To exchange electronic messages and computer files over a communications network, such as the Internet. (noun) An electronic message.
Extension Part of a file name. The extension is a period followed by (usually) three characters that tells the operating system which program to use with the file. For example, the extension for a Word document is .doc. The program often assigns the extension to the file name to identify in what program it was created.
FAQ Frequently Asked Questions. Acronym often seen on web sites to explain features.
File Information saved in a computer. A file can be either data (a document), or a collection of commands or instructions (a program).
File Name The name of a file. Windows allows up to 256 characters, including spaces, for the file name plus a period and the extension.
Flash Drive See USB Flash Drive.
Flash Memory See Non-Volatile Memory.
Highlight See Select
Folder Folders are collections of files and sub-folders. You should organize and name your folders so that files are easy to locate.
Font The term applied to styles of letters, numbers, punctuation marks and symbols. For example, the font used in this document is called Times New Roman. This is another common font, called Arial.
Format (document) The appearance of text (such as font or paragraph alignment), images (such as borders and backgrounds), and pages (such as margins).
Format (disk) To prepare a disk for holding information. Formatting a disk deletes all information that was previously on it.
GB Gigabyte. A unit of information equal to about a billion bytes in a computer.
Graphics Pictures or images created using a program, camera, or scanner.
Hard Drive or Hard Disk The permanent data and program storage in a computer. It consists of one or more rigid plates with magnetic coating. The data on the hard disk should be backed up regularly.
Hardware The physical parts of a computer, including the peripheral equipment such as printers, modems, and mouse devices.
Home Page The main page for a web site, usually seen first when the web site is accessed. Also, the page you select as the opening page for your browser.
Hover To place the mouse pointer over an item without clicking on it.
HTML Hypertext Mark-up Language, the programming language used to create web pages. HTML files have the extension .htm or .html.
Hyperlink (link) A highlighted, colored, or underlined word, phrase or other graphic on a web page that, when clicked, will cause a new page to be displayed.
Icon A small image or graphic displayed on the screen to represent some item (such as a folder or software program), action or command (such as print or copy) that can be activated by the user. Icons represent the file, folder, program or action rather than displaying the entire item.
Insert To add new information between existing information, such as inserting a word in a sentence, or inserting a row in a spreadsheet or database.
Insertion Point The vertical line that marks where information will be entered when typing text or pasting from the clipboard.
Internet A vast, world-wide communications network between computers, including email and the World Wide Web.
Keyboard The set of keys used for typing text, scrolling, and controlling other functions in programs.
KB (Kilobyte) A unit of information equal to 1,024 bytes.
Link See Hyperlink.
List Box A small window in a dialog box with text or graphic choices. Some list boxes open to show a longer list when clicked. Other list boxes are scrolled through using scroll arrows.
MB (Megabyte) A unit of information equal to about one million bytes.
Memory A temporary information storage area in the circuits of the computer. A camera’s memory is stored on removable memory cards
Menu Bar A rectangular bar at the top of an application’s window that displays available menus. Clicking on the menu name displays a list of options or commands.
Modem Modem is short for modulator/demodulator and is the device in or attached to the computer that permits data transmission over telephone or cable lines. Modems are needed to connect to the internet, whether using dial-up, DSL, cable, or satellite.
Motherboard Refers to the circuit board in the computer which contains the microprocessor, memory, the expansion slot connectors and other circuitry which makes up the heart of the computer.
Mouse A hand-held movable device used to point to and activate computer functions. Both mice and mouses are used for the plural.
Mouse Pointer See Pointer
Non-Volatile Memory Memory storage that does not lose its information when the power is turned off, as opposed to RAM which does lose the information. Flash Memory is the most common type of non-volatile memory, used in USB Flash Drives, camera memory cards, cell-phones, and many other items.
Notification Area The area on the taskbar to the right of the taskbar buttons. The notification area displays the time and can also contain shortcuts that provide quick access to programs, such as Volume Control and Power Options.
Open To activate a program or data file so it is visible and usable on the screen.
Operating System The software that controls the functions of the computer, including starting and stopping, organizing files and folders, saving and printing files, and managing multiple applications simultaneously. The Microsoft Windows operating system is used in over 90% of personal computers.
Pixel picture element. Refers to one of the thousands of dots that make up a picture.
Pointer (Mouse Pointer) The symbol (arrow, I-bar, or other) directed by moving the mouse.
Points and Point Size The height of a printed character is specified in units called points. There are 72 points per inch. Also known as font size.
Program See Application
Quick Launch Bar A toolbar to the right of the Start button on the task bar. A program can be started with a single click on a button on the Quick Launch Bar, and the Quick Launch Bar is always visible, while icons on the desktop may be hidden by other windows. The display of the Quick Launch Bar can be turned on and off.
Radio Button A small circle that contains a dot when it is selected. Each radio button represents an option or choice. Only one radio button in a category may be selected at a time. Clicking a radio button selects a specific function and deselects the other functions. Also see Check Box
RAM Random Access Memory. Program and data information is moved into this temporary storage for use by the microprocessor. Information that resides in RAM must be saved on a disk prior to turning off the computer or the information will be lost.
Readme A file on a program’s installation disc that presents updated or important information.
ROM (Read Only Memory) Permanent memory that stores key data used by a computer. It can be read, but not modified. The contents of this memory are retained after the computer is turned off.
Save To copy a file from temporary storage (RAM) to permanent storage (a hard disk or removable disk).
Screen The display shown on the computer monitor.
Select To specify a block of data, text, or graphics by highlighting it using the mouse or keyboard. To perform an operation, such as copying or modifying the format, the desired data must be selected
Scroll To move through text or graphics (up, down, left or right) in a window in order to see parts of a document or list that cannot fit on the screen. Scrolling is controlled with a scroll bar and scroll arrows.
Software Instructions (programs) that make computer hardware perform tasks.
Start Button The button at the far left of the task bar, labeled start in Windows 95, 98, ME, and XP. Clicking this button gives access to the major functions of Windows, including All Programs, recently used programs, My Computer and My Documents directories, and the button to turn off the computer.
Sub-folder A folder within another folder.
System See Operating System
Tab (dialog boxes and windows) Part of a dialog box or window that resembles tabs in a notebook or file divider. Tabs allow moving between different sections of the dialog box or window.
Tab (word processing) Using a tab stop to indent or begin a column of text.
Tab (keyboard) The T key at the left side of the keyboard that is used to insert a tab character in a word processing document or to move between fields in a form.
Task Bar The bar at the bottom of the desktop screen with the Start button on the left, followed by the Quick Launch bar (if turned on), the taskbar buttons, and the Notification Area with the clock.
Task Bar Buttons Each application window is represented by a button on the task bar. Click a taskbar button to switch to that application. When the application window is minimized, it only appears as the taskbar button.
Thumb Drive See USB Flash Drive.
Title Bar The horizontal bar at the top of a window that shows the title of the window. On most windows, the title bar also contains the program icon, and the Maximize, Minimize, and Close buttons. The title bar is also used to move a window on the screen.
Toolbar A row, column or block of buttons or icons, which, when clicked, activate specific functions of the application.
URL (Uniform Resource Locator) The address of a Web page on the Internet.
USB (Universal Serial Bus) A standard connector for attaching peripheral hardware to a computer. Most printers, scanners, cameras, and many mice and keyboards attach with USB connectors.
USB Flash Drive A compact (3/4” x 2”) portable memory storage device, using a USB connector. This is the most common way of carrying files between computers today.
Web (World Wide Web) Part of the Internet. A system for exploring the Internet by using hyperlinks to view web pages. The World Wide Web is explored using a browser.
Web Page A file containing text and graphic data displayed on a web site.
Web Site A group of related web pages.
Window An area on the screen in which an program or document is viewed.
Word Processor An application designed to produce letters, memos, etc., in which one may create, format and edit text and print and save the document.
Word Wrap Automatically continues to wrap text from the end of a line to the beginning of a new line as you type.