In a widely expected move, Steve Jobs resigned Wednesday as Apple's chief executive and handed over the reins to Tim Cook, who was the company's chief operating officer and had been assuming Job's role in his absence.

The news comes at a time when Apple's iPhone 5 has been speculated to arrive on Sprint's network this fall, while iPad 3 and iOS 5 are set to be launched this year.

Jobs, who has been on medical leave since January, becomes chairman of the board and Cook too will join the board, effective immediately. 

Steve's extraordinary vision and leadership saved Apple and guided it to its position as the world's most innovative and valuable technology company, said Art Levinson, chairman of Genentech, on behalf of Apple's Board.

Steve has made countless contributions to Apple's success, and he has attracted and inspired Apple's immensely creative employees and world class executive team. In his new role as chairman of the board, Steve will continue to serve Apple with his unique insights, creativity and inspiration, Levinson said.

The board has complete confidence that Tim is the right person to be our next CEO, added Levinson. Tim's 13 years of service to Apple have been marked by outstanding performance, and he has demonstrated remarkable talent and sound judgment in everything he does.

Following is the letter from Steve Jobs to Apple's board of directors:

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.

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.

End of an Era:

Though Jobs' resignation signals an end of an era, analysts have expressed confidence in Cook.

We are saddened to hear about Steve Jobs stepping down from his position as CEO of Apple. However, we remain supremely confident in Tim Cook as a worthy and capable successor who has already been managing the day to day operations. While saddened, we are not surprised to hear about Steve's departure as this had been speculated about for some time, Webush Morgan analyst Scott Sutherland wrote in a note to clients.

As COO, Cook was previously responsible for all of the company's worldwide sales and operations, including end-to-end management of Apple's supply chain, sales activities, and service and support in all markets and countries.

He also headed Apple's Macintosh division and played a key role in the continued development of strategic reseller and supplier relationships, ensuring flexibility in response to an increasingly demanding marketplace.