The visionary who revived the company when he returned as CEO in 1997 has been on medical leave since January. Here is his statement today:

"August 24, 2011–To the Apple Board of Directors and the Apple Community:

"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.

"I hereby resign as CEO of Apple. I would like to serve, if the Board sees fit, as Chairman of the Board, director and Apple employee.

"As far as my successor goes, I strongly recommend that we execute our succession plan and name Tim Cook as CEO of Apple. [Cook joined Apple shortly after Jobs returned to Apple in 1997 and has been responsible for day-to-day operations during his medical leave.]

"I believe Apple’s brightest and most innovative days are ahead of it. And I look forward to watching and contributing to its success in a new role.

"I have made some of the best friends of my life at Apple, and I thank you all for the many years of being able to work alongside you."

In 2004, Jobs was diagnosed with pancreatic cancer, and he underwent a liver transplant in 2009. He has said very little about his health.