Evolution of an Apple revolution

•1971: Steve Jobs, age 16, meets Steve Wozniak, 21, through a mutual friend.

•1974: Mr. Jobs works at video-game maker Atari, and Mr. Wozniak, the engineering wizard, at Hewlett-Packard.

•1975: Jobs and Wozniak attend meetings of the Homebrew Computer Club, a group of electronics enthusiasts who work on computers for home use.

•1976: Jobs and Wozniak raise $1,300, most of it through the sale of Jobs's Volkswagen bus and Wozniak's scientific calculator, to build their first computer. Along with Ronald Wayne, they found Apple Computer Company (Wayne sells his stake two weeks later). The Apple I, created in Jobs's garage, goes on sale for $666.66.

•1977: Apple is formally incorporated as Apple Computer Inc. The company launches the Apple II, the first mass-marketed personal computer and one of the first to generate color graphics.

•1980: Apple III, aimed at the business market, debuts – with numerous problems. The company orders a recall. In a management shake-up, Mike Markkula becomes Apple president and Jobs the chairman. Late in the year, the company goes public, with an opening stock price of $22 a share. It generates more capital than virtually any other initial public offering to that date.

•1981: Wozniak takes a leave of absence after being injured in the crash of a private plane.

•1982: Apple becomes the first personal computer company to reach $1 billion in sales.

•1983: Lisa, pioneering the use of a mouse to control a computer, debuts. In a quest to be user-friendly, it also displays pictures (icons) on the computer screen to substitute for keyboard commands. It founders in the marketplace. Jobs recruits John Sculley from PepsiCo to be Apple president and CEO.

• 1984: Apple launches the Macintosh with the iconic "1984" commercial at the Super Bowl, which depicts a woman hurling a hammer at a Big Brother-like figure on a screen, celebrating nonconformity.

•1985: Jobs is ousted from Apple after a boardroom fight with Mr. Sculley. He and Wozniak both resign. Later in the year, Jobs forms Next Inc. (later called NeXT), to make high-end computers for universities.

•1986: Jobs buys "The Graphics Group" (which becomes Pixar Animation Studios) from George Lucas for $10 million.

•1989: The first NeXT computer, also known as The Cube, goes on sale for $6,500. It struggles in the marketplace but introduces several innovations.

•1993: Apple introduces the Newton, a hand-held message pad. Sculley resigns as CEO as the company restructures. Unprofitable NeXT decides to focus on software instead of building computers.

•1995: Pixar's first film, "Toy Story," created entirely on computers, is released, becoming the highest-grossing domestic movie of the year.

•1996: Apple buys NeXT for $430 million. Jobs becomes an adviser to Apple chairman Gilbert Amelio.

•1997: Apple's revenues plummet. Jobs returns as interim CEO and chairman of Apple.

•1998: Apple launches the iMac, a teal-and-white translucent computer (and later in all kinds of candy colors) that puts the monitor and processor in one unit. Sales boom. Apple returns to profitability.

•2000: Jobs formally becomes CEO.

•2001: Apple makes its first venture into consumer electronics with the iPod, a portable MP3 player, that revolutionizes how people listen to and collect music. It eventually becomes one of the most successful gadgets of all time.

•2003: Apple launches the iTunes store, giving people an easy way to buy music online.

•2004: Jobs undergoes surgery for pancreatic cancer.

•2005: Apple broadens the iPod line with the tiny Nano and with a version that can play video.

•2006: Disney acquires Pixar for $7.4 billion.

•2007: Apple unveils the iPhone, one of the first smart phones without a keyboard. Crowds line up at stores to buy them.

•2009: Jobs takes a medical leave and undergoes a liver transplant.

•2010: Apple launches the iPad, a touch-screen tablet computer that ushers in a new genre of mobile computing. It's an instant phenomenon.

•Aug. 9, 2011: Apple briefly surpasses ExxonMobil as the world's most valuable company based on its stock value.

•Aug. 24, 2011: Jobs steps down as CEO, due to health concerns, and takes over as chairman.