Port

A physical input/output socket on a computer to which you can connect a peripheral device.

Power-on diagnostics

Tests stored in a computer’s ROM that the computer runs to check its internal circuitry, peripheral device configuration, and operating status each time you turn it on or reset it.

Processor speed

See Operating speed.

Program

A file containing coded instructions that tell the computer what to do and how to do it. See also File.

Prompt

A message displayed by the operating system or a program to request information from you or tell you what action to perform next. See also Command prompt.

RAM

Random Access Memory. The portion of the computer’s memory used to run programs and store data while you work. All data stored in RAM is erased when you turn off or reset the computer; so you must store any data you want to keep on disk.

18 Glossary