At each pass, he faced incredible skepticism; a rational analysis would have predicted defeat. But he persevered. His legion of admirers — and critics — are now wishing him a full recovery now that he begins a six-month medical leave from Apple. And whatever suffering his present physical condition is causing, the mental anguish of acknowledging that he is not well enough to lead his company must be its own particular pain.

Every hero's strength is usually also a flaw. With Jobs, it is his relationship with the truth. That spirit of denial is exactly what has led him to reinvent industry after industry for the past three decades. But the truth about his own declining health — at first flatly denied, then grudgingly confirmed but downplayed, and now confirmed as grave — cannot be changed simply through the power of belief.

In 2005, two years after he was first diagnosed with pancreatic cancer, Jobs waxed philosophical about death in a commencement address he delivered at Stanford University:

Remembering that I'll be dead soon is the most important tool I've ever encountered to help me make the big choices in life. Because almost everything — all external expectations, all pride, all fear of embarrassment or failure - these things just fall away in the face of death, leaving only what is truly important. Remembering that you are going to die is the best way I know to avoid the trap of thinking you have something to lose. You are already naked. There is no reason not to follow your heart.

Therein lies the contradiction: In his health, Jobs does indeed have something to lose. And following his heart, which surely tells him to ignore the problem, in this matter is dangerous.

Jobs's track record, though, makes his defiance understandable. Having overcome so many other obstacles, why would he not think the aftereffects of cancer would prove trivial, too? Here's the career which helped feed Jobs's hubris:

1976 Jobs, a college dropout, founds Apple Computer with engineer Steve Wozniak. They introduce the Apple I, a personal computer for hobbyists.

1977 Apple introduces the Apple II, one of the first personal computers with a color display. Over the next 16 years, Apple sells more than 5 million units.

1984 Jobs, with a crew of self-described "pirates" pulled from other projects at Apple, introduces the Macintosh, a computer with a graphical user interface and a mouse.

1985 Apple's board fires Jobs. He founds Next Computer.

1986 Filmmaker George Lucas sells Pixar, then an animation-software startup, to Jobs.

1995 Pixar releases its first digitally animated feature film, Toy Story, and goes public; Jobs owns 80 percent, a stake worth nearly $600 million. (Pixar movies make regular appearances in Jobs's presentations for Apple, like this one in 1999.)

1996 Apple buys Next for $430 million; Jobs becomes an advisor to hapless CEO Gil Amelio.

1997 Having lost faith in Amelio, Jobs sells his entire stake in Apple. Amelio is forced out. Jobs becomes interim CEO.

1998 Jobs unveils the iMac.

2000 Jobs drops the "interim" bit and becomes Apple's CEO.

2001 A month after 9/11, to little notice, Jobs introduces the iPod.

2003 Apple launches the iTunes Music Store, with a little help from rock-star friends like Mick Jagger.

2005 The iPod Nano comes out, unveiled by Jobs as an aside at the launch of a now-forgotten iPod-phone combination.

2006 Disney buys Pixar; Jobs's stake is now worth $4.6 billion.

2007 Jobs unveils the iPhone.

2008 The MacBook Air and the iPhone 3G are announced. Observers notice Jobs's dramatic weight loss.

(Photos by AP and Getty Images)

Yahoo turns 15 next month. The site first went live, on a Stanford Unversity server, in January 1994. The years since fall neatly into two halves: the first, its dizzying rise from a campus trailer to $100 billion goliath; the second, its equally stupefying fall. Here's a recap of the past decade and a half.

1994


Stanford graduate students Jerry Yang and David Filo create Jerry's Guide to the Web, a directory of links to websites, in January. In April, they rename it Yahoo.

1995
Yahoo incorporates in March. Sequoia Capital, a VC firm which invested in Apple and Cisco, buys in. In August, it starts selling ads. The Web is now a business.

1996
Yang and Filo appear on the cover of Wired; Yahoo goes public, beating most of its Web rivals to the punch. But the early stock offering also means Yang and Filo are now subject to the whims of shareholders. Yahoo Japan, a partly-owned subsidiary, launches.

1999


Yahoo spends billions of dollars on GeoCities and Broadcast.com, acquisitions that later prove a waste — save for turning Broadcast.com founder Mark Cuban into a billionaire, allowing him to buy the Dallas Mavericks and become an ongoing source of entertainment.

2000
Yahoo's market cap peaks in January above $100 billion. The stock begins a long slide after the dotcom bubble pops. In June, it signs a deal to have Google provide its search results. In retrospect, this is where everything started to go wrong.

2001
After a three-month search, Yahoo hires Terry Semel, the former head of the Warner Bros. studio, as CEO.

2002
Yahoo announces plans to buys Inktomi, a search engine.

2003
Semel follows the Inktomi buy with Overture, which sells search advertising, in a strategy to beat Google.

2004
Yahoo hires Lloyd Braun, a former ABC executive, to run its media operations. Hilarity ensues, as Braun proves laughably unsuited to the job and the online medium, and Yahoo's push into Hollywood-style content production proves a flop.

2005


Yahoo has secret talks to buy Flickr, the photo-sharing site. That deal happens. Microsoft has secret talks to buy Yahoo. Nothing happens. Yahoo reaches the peak of its post-bubble influence — but the surge proves illusory.

2006
Microsoft has secret talks to buy Yahoo. Nothing happens. Lloyd Braun "quits."

2007
Microsoft has secret talks to buy Yahoo. Nothing happens. Semel resigns. Yang replaces him.

2008
In a phone call in late January, Microsoft CEO Steve Ballmer bids $44.6 billion for the company — sort of. Semel quits the board that night. Yang and the board dither. In February, Yahoo lays off 1,000 employees. Microsoft eventually walks away. Corporate raider Carl Icahn buys shares, raises a stink, and gets three board seats. Yang steps down as CEO, pending a search for his replacement. In December, Yahoo lays off another 1,500 employees — 10 percent of its workforce. There's talk that Microsoft might be having secret talks to buy Yahoo. Nothing happens.

(Photo of Yang and Flickr's Caterina Fake and Stewart Butterfield by Ross Mayfield)

• Microsoft's first acquistion target in search wasn't Yahoo. Back in 2003, rumor said Microsoft would purchase Google. The New York Times reported that before Google's IPO, the companies talked about a buyout but it never went anywhere. Instead, Microsoft signed a search deal with Looksmart. Oops.
• Rumors of a Microsoft-Yahoo merger began in earnest in early 2006. In January, the Los Angeles Times reported Yahoo turned down an $80 billion offer from Microsoft. Yahoo shares spiked on the news. You may have noticed the share value has since declined.
• By mid-2006, the rumors were back, but Ziff-Davis's Mary Jo Foley reported that Microsoft only expressed interest in taking a stake in Yahoo's search business.
• In July 2006, Microsoft CEO Steve Ballmer said during an earnings call that a Yahoo acquisition would not help Microsoft get competitive in search. "There is no acquisition path out," he said.
• By May 2007, rumors were back. This time the number was $50 billion. Yahoo shares rose almost 10 percent on the news, closing at $30.98. Just under the $31 Microsoft offered today,

• November 1996 Yahoo and MTV announce the creation of UnfURLed, "the ultimate guide to music on the Web." The site is promised to launch in January 1997.
• January 1997 UnfURLed does not launch.
• July 1997 UnfURLed launches, six months late. The site later disappears, forgotten.
• February 1999 Viacom acquires Imagine Radio, a service which lets users listen to preprogrammed music channels, or create their own. (If that sounds a lot like Last.fm or Pandora, that's because it was a lot like those sites.)
• May 1999 Viacom acquires SonicNet, an online music-news and information site.
• August 1999 Amid Internet fervor, Viacom creates the MTVi Group as a rollup of its Internet websites, hoping to take it public to cash in on the market for Internet stocks.
• August 2000With an IPO off the boards, Viacom reorganizes MTVi, giving control over websites like MTV.com and VH1.com back to their respective cable channels.
• 2001-2004 MTV does nothing interesting with Internet music for five years or so, as best we can tell.
• April 2005 MTV launches Overdrive, a broadband "channel." MTV later brags about how many "video streams" Overdrive serves, not noticing the complete apathy with which music fans greet it.
• July 2005 News Corp. swoops in and inks a deal to buy the parent company of MySpace. Viacom is widely reported to have been interested in buying MySpace, which gained popularity by embracing music on user profiles and getting bands to use the site to communicate with fans.
• January 2006 Microsoft and MTV launch Urge, an online music store.
• August 2006 Google and MTV announce an experimental deal to distribute videos over Google's AdSense network. The experiment, apparently a failure, dissolves quietly.
• September 2006 Viacom CEO Tom Freston, a longtime MTV exec, is fired, reportedly for missing the chance to buy MySpace. Later that month, Microsoft knifes MTV in the back by announcing its Zune player and companion store, rendering Urge pointless.
• August 2007 MTV merges Urge into RealNetworks' also-struggling Rhapsody music service.

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