What Is UNIX?

UNIX once referred to a specific operating system. However, today it is not a single operating system, but rather a large family of closely related operating systems. These different operating systems are sometimes known as UNIX variants, or UNIX-like operating systems. All these operating systems are built using a collection of enabling technologies that were originally developed in the 1970s at AT&T Bell Laboratories and at the University of California, Berkeley They have much in common and share a set of utilities and programs. However, each variant has its own peculiarities and differs from other variants particularly in its kernel, or inner code, and in specialized features.