.ORG - When these letters appear as the last part of a Web address, it indicates that the host computer is run by a nonprofit institution, usually in the United States.

Offline - When a computer is not connected to a host system or the Net, it is offline.

ON/OFF Hook - A descriptive term referring to manually lifting a telephone receiver (taking it OFF Hook) and replacing it (going ON Hook). OFF Hook produces a busy signal on the phone line.

Online - You are online if you are working on your computer while it is connected to another computer This is known as being “connected”.

Operating System (OS) - The most important program that runs on a computer. Every general-purpose computer must have an operating system to run other programs. Operating systems perform basic tasks, such as recognizing input from the keyboard, sending output to the display screen, keeping track of files and directories on the disk, and controlling peripheral devices such as disk drives and printers. Windows, Unix, MSDOS, etc. are Operating Systems.