UNIX

UNIX is an operating system, a set of the software that controls a computer's basic function. First created in 1969 at AT&T's Bell Labs, it has been popular in numerous commercial and free variants since the 1970s. As AT&T was obliged by an antitrust decision to license Unix freely, multiple versions developed, and Unix became an important tool for the open-source community.

Like Windows, Unix-like systems allow multitasking, multiprocessing, and multiple user accounts. Unlike Windows, they are composed of numerous small programs that run over a common kernel.

Although Microsoft's Windows operating system dominates the personal computer market, the two most popular competitiors, OS X and Linux, are UNIX-like. Flavors of UNIX such as Android and iPhone OS are more popular on mobile phones, and UNIX-like systems such as Linux run much of the Internet as well as most supercomputers. Plum's servers also run on Linux.