Apple CEO Steve Jobs died on Wednesday. He was 56.

Jobs died after a protracted and at times public battle with cancer. He took three medical leaves of absence from his Apple CEO post before permanently handing over the position to Tim Cook, then the chief operating officer.

When he stepped down, Jobs said if there ever came a day when I could no longer meet my duties and expectations as Apple's C.E.O., I would be the first to let you know. Unfortunately, that day has come.

Even after his resignation, he remained involved with the company.

His death comes just one day after Apple unveiled its iPhone 4S in the Let's Talk iPhone Event.

Under Jobs' watch, Apple grew from a stagnant computer maker to a juggernaut in the consumer devices market. In the process, it became the most valuable publicly traded company in the world.

Apple, especially earlier in its history, has been a longtime competitor of Microsoft. It initially lost the personal computers war to Microsoft but then more than made up for it by its success with the iPod, iPhone, and iPad. All three products were developed under Jobs' watch.

On news of his death, Microsoft founder Bill Gates issued the following statement through Facebook:

I'm truly saddened to learn of Steve Jobs' death. Melinda and I extend our sincere condolences to his family and friends, and to everyone Steve has touched through his work.

Steve and I first met nearly 30 years ago, and have been colleagues, competitors and friends over the course of more than half our lives.

The world rarely sees someone who has had the profound impact Steve has had, the effects of which will be felt for many generations to come.

For those of us lucky enough to get to work with him, it's been an insanely great honor. I will miss Steve immensely.

Gates, 55, founded Microsoft in 1975, one year before Jobs founded Apple.