Unix turns 40

Forty years ago this summer, a programmer sat down and knocked out in one month what would become one of the most important pieces of software ever created.</p>

• The past, present and future of a revolutionary OS
• Illustrated Unix family tree
• Unix Timeline

As fun as it is to revisit the past, the important metric is the direction of the future.

"Unix has had a long and lively past, and while it's not going away, it will increasingly be under pressure," says Gartner analyst George Weiss. "Linux is the strategic 'Unix' of choice." Although Linux doesn't have the long legacy of development, tuning and stress-testing that Unix has seen, it is approaching and will soon equal Unix in performance, reliability and scalability, he says.