UNIX and the C programming language were developed by AT&T and distributed to government and academic institutions, which led to both being ported to a wider variety of machine families than any other operating system. As a result, UNIX became synonymous with "open systems". Widely used in both servers and workstations. The UNIX environment and the client-server program model were essential elements in the development of the Internet and the reshaping of computing as centered in networks rather than in individual computers.

UNIX was designed to be portable, multi-tasking and multi-user in a time-sharing configuration. The UNIX operating system consists of many of utilities along with the master control program, the kernel. The kernel provides services to start and stop programs, handles the file system and other common "low level" tasks that most programs share.

The courseware in this UNIX OS category provides coverage for every level of user from the desktop application user to the system administrator working in complex enterprise environments.