The mother-tongue of the Net. The operating system is found on many of the Net's routers and servers.

Computer operating system developed at ATT Bell Laboratories in 1970 that provided the basis of software and research for creating the Internet as we know it today. Many Internet servers still run Unix. See also serverand shell accounts.

A Multitasking Operating System developed in 1969. The are many variants of Unix. Written in the C Programming Language it is very portable - running on a number of different computers. Unix is the main operating system used by Internet host computers.