Unix is one of the most popular operating systems worldwide because of its large support base and distribution. It was originally developed as a multitasking system for minicomputers and mainframes in the mid-1970s. It has since grown to become one of the most widely used operating systems anywhere, despite its sometimes confusing interface and lack of central standardization.

The real reason for Unix’s popularity? Many hackers feel that Unix is the Right Thing—the One True Operating System. Hence, the development of Linux by an expanding group of Unix hackers who want to get their hands dirty with their own system.

Versions of Unix exist for many systems, ranging from personal computers to supercomputers such as the Cray Y-MP. Most versions of Unix for personal computers are quite expensive and cumbersome. At the time of this writing, a one-machine version of AT&T’s System V for the 386 runs at about $US1500.

Linux is a freely distributable version of Unix, originally developed by Linus Torvalds, who began work on Linux in 1991 as a student at the University of Helsinki in Finland. Linus now works for Transmeta Corporation, a start-up in Santa Clara, California, and continues to maintain the Linux kernel, that is, the lowest-level core component of the operating system.

Linus released the initial version of Linux for free on the Internet, inadvertently spawning one of the largest software-development phenomena of all time. Today, Linux is authored and ...