What is Unix?

UNIX is an operating system. The job of an operating system is to orchestrate the various parts of the computer -- the processor, the on-board memory, the disk drives, keyboards, video monitors, etc. -- to perform useful tasks. The operating system is the master controller of the computer, the glue that holds together all the components of the system, including the administrators, programmers, and users. When you want the computer to do something for you, like start a program, copy a file, or display the contents of a directory, it is the operating system that must perform those tasks for you.

More than anything else, the operating system gives the computer its recognizable characteristics. It would be difficult to distinguish between two completely different computers, if they were running the same operating system. Conversely, two identical computers, running different operating systems, would appear completely different to the user.

UNIX was created in the late 1960s, in an effort to provide a multiuser, multitasking system for use by programmers. The philosophy behind the design of UNIX was to provide simple, yet powerful utilities that could be pieced together in a flexible manner to perform a wide variety of tasks.