And just like that, Steve Jobs has stepped down from his throne as CEO of Apple and handed the scepter to the current chief operating officer, Tim Cook. You can’t say no one saw it coming. Jobs has been on a medical leave of absence since January 17, 2011 for undisclosed reasons (he had a liver transplant in April 2009 after battling pancreatic cancer for years).
Cook’s been with Apple since 1998, a former IBM guy who’s been tagged as the heir apparent for years, filling in each time Jobs took a medical leave of absence and handling day to day operations since 2005. And Cook’s company positioning has been mostly good news for Apple: Each time he grabs the wheel, Apple’s stock goes up (Apple’s stock was down 5% in after hours trading, but that’s really no surprise, given the magnitude of this announcement).
(MORE: Steve Jobs Resigns As Apple CEO, Will Become Chairman)
No, this doesn’t mean Jobs is quitting Apple. He’s simply descending from Apple’s loftiest heights and requesting that he be allowed to serve “as Chairman of the Board, director and Apple employee.” In fact Apple’s already obliged. The company moved immediately to name Cook as CEO, per Jobs’ wishes, and elected Jobs to the chairman position he requested.
So yes, for reasons presumably health-related (the endless speculation continues), the close of another era’s at hand. The first kicked off all the way back in 1976, when Jobs, 21, and Steve Wozniak, 26, founded Apple. Just about anyone in their late thirties today probably remembers the Apple II (released in 1977), the first home “personal computer” with color graphics, a staple in school classrooms for years. And in 1984, we tuned into Super Bowl XVIII and said hello to the Macintosh (remember the hurtling sledgehammer?), the computer that wore a smiley face before turning them sideways in instant messaging clients was hip. You could have one with a generous (in 1984) 512K for a bargain $3,195.
And then things went strangely south for Jobs and Apple. Jobs had tapped Pepsi to bring in John Sculley as Apple’s CEO in 1983, but when industry sales plummeted toward the end of 1984, the two clashed, leading to a nasty power struggle that culminated in Apple’s board of directors asking Jobs to resign in 1985. After leaving Apple, Jobs went on to co-found animation studio Pixar in 1986 and NeXT Inc., a company that built futuristic UNIX-like computers. Everyone knows what happened with Pixar, but it was at NeXT that the forerunner of the Mac’s next-gen operating system, OS X, was born.
When Apple purchased NeXT for $429 million in 1996 and brought Jobs back as quasi-CEO—the advent of “era number two”—NeXT’s operating system, dubbed “NeXTstep,” essentially became what we now know as OS X, the tenth iteration of Apple’s Macintosh computer operating system.
The rest, as they say, is history. Over the following 15 years Jobs took Apple from its position as a diminished technological player with a dwindling computer market share to a global powerhouse and multimedia empire that, as of last April, managed to surpass Exxon Mobil as the most valuable company in the world. Think of all that’s happened in those past 15 years: PowerMacs and PowerBooks, MacBooks, MacBook Pros and MacBook Airs, iPods and iTunes, iPads, iPhones and Apple TVs, all perennially trotted out by Jobs himself in his signature black turtleneck and jeans.
It’s anyone’s guess how much of Jobs’ decision to resign now was health-related, and given his health’s ties to investor confidence in Apple’s share price, it’s likely we won’t know unless (or until) something happens that can’t be kept hidden.
(PHOTOS: The Long Extraordinary Career of Steve Jobs)
Matt Peckham is a reporter at TIME. Find him on Twitter at @mattpeckham or on Facebook. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.