format: To divide a disk into sections where information can be stored. Disks must be formatted before you can save information on them. Also called initialize.

form feed: The way perforated printer paper is pulled into position for printing. Compare friction feed.

formula: An equation. By writing formulas to define relationships between the various numbers in your spreadsheet, you can try out different numbers, and the formulas will recalculate all the totals for you.

FORTH: A programming language.

Fortran: A programming language.

40-column display: The number of characters per line that are displayed on the screen. The options are 40 and 80 columns.

free-form data base: A data base that lets you enter information in paragraph form (instead of by categories) and designate key words that you can search for later.

friction feed: The way a printer moves individual sheets of paper into position for printing. It's the same way typewriters move paper into position. Compare form feed.

full-duplex modem: A modem that echoes information it receives back to the sending computer. Most commercial information services are full-duplex.

function: A built-in formula you can use to calculate an average, a square root, and the like.

function key: A key that tells the application to carry out a particular activity or function (print a document, save a document, and so on). Some applications use the number keys on the numeric keypad as function keys.

garbage: A string of meaningless characters that bears no resemblance to your document. It's an indication that your computer and peripheral device are using different bauds or data formats.

graphics: Information presented in the form of pictures or images.

graphics mode: A way of displaying text and graphics on the screen. In graphics mode, images are formed by patterns of dots.

graphics tablet: A device for drawing pictures. A special pen sends out signals that are detected by wires in the tablet and sent as X and Y coordinates to the screen.

hacker: A person who is on a first-name basis with RAM, ROM, and the microprocessor. A person who'd rather write application programs than use store-bought programs.

half-duplex modem: A modem that does not echo information it receives from the sending computer.

hand controls: Computer accessories used mainly in games to move creatures and objects. Also used in simulation applications.

handshake signal: A signal that regulates the flow of data between the computer and peripheral devices.

hard disk: A storage device that can hold the equivalent of dozens of 3.5-inch disks.

hardware: Those parts of the computer that you can see and touch. The computer and the machines that attach to it: the disk drive, printer, and other peripheral devices. Compare software.

header: Text that appears at the top of every page or every other page of a document. Compare footer.

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Glossary