But Jobs' health increasingly took center stage when he appeared in public. By 2006 he was already noticeably thinner, and after his 2008 Macworld keynote, with observers speculating about his health, Apple was forced to react. It said Jobs was suffering from a "common bug" and taking antibiotics for it. Jobs and others said his health issues were "not life-threatening" and did not involve a recurrence of pancreatic cancer.

Later that year Bloomberg posted Jobs' obituary to its newswire by accident (news outlets often have obituaries for elderly public figures -- or those known to be unwell -- written and ready to run.) Although the story was missing a date and cause of death, it fired up more speculation about his health and generated speculative stories about a future at Apple without Jobs.

In January 2009 Jobs, who was always unwilling to share private details of his life, said in a letter that a hormone imbalance had been causing his noticeable weight loss. Just a week or two later he said he would be taking a six-month leave of absence from Apple to deal with his medical condition, which he said had worsened. Cook, who was then COO, handled day to day operations in Jobs' absence. It was revealed later that Jobs had while on hiatus.

He was back at work on schedule in late June, though the company said he would work from home part of the time. In January 2010 he appeared on stage in San Francisco to announce the iPad, and was in the spotlight again in September to launch a new version of Apple TV.

In January 2011, Jobs said he would be taking another medical leave of absence, not saying this time how long he would be away. But while on leave, he appeared on stage at a San Francisco event in March to introduce the iPad 2 , and in June to introduce the iCloud and iOS 5 at company's Worldwide Developers Conference. By the June event, Jobs, looked gaunt, though he spoke with enthusiasm about the new iPad. Two months later, he stepped aside as CEO, writing to employees: "I have always said if there ever came a day when I could no longer meet my duties and expectations as Apple's CEO, I would be the first to let you know. Unfortunately, that day has come."