Apple didn’t bring Steve Jobs back per se. In truth, the company purchased NeXT and its OpenStep operating system in 1996, with the company cofounder along for the ride as an advisor. Jobs pushed out Gil Amelio in 1997 following a boardroom coup, but it would take four more years for the son of OpenStep, nee Mac OS X, to replace Apple’s original Classic operating system.

On March 24, 2001, a decade ago, Apple launched Mac OS X v10.0 “Cheetah” and, honestly, it kind of blew. Whereas it was a lot more stable than Classic (what wasn’t?), Cheetah was slow, native software was non-existant and the still incomplete Aqua interface was so beautiful people skinned it.

See also: Kodiak: OS X was born a bear

Nevertheless, protected memory and real multitasking won the day. Moreover, OS X is still winning the day, with Mac unit volume growing by double digits every quarter and iOS, with its OS X heart, defines the smartphone and tablet segments.

So Happy Birthday, Mac OS X, and many happy returns to you and your fathers…

via Wikipedia’s Mac OS X History