Virtually overnight Tim Cook has become one of the world's most powerful men, but who is he?

Apple's board on Wednesday elected Cook as CEO after tech visionary Steve Jobs abruptly resigned his post. Jobs, 56, who has battled pancreatic cancer in the past, was elected chairman.

Cook, a 13-year Apple veteran, in April was named America's most influential gay person by glossy Out.

Now, as he prepares to take over the reigns at Apple, the question is, who is the world's most powerful gay man?

Cook's ascension wasn't a fluke. The 50-year-old executive has been groomed for the role for some time now. He temporarily filled in for Jobs in 2004, 2009 and 2011.

Before boarding Apple's executive team, Cook spent time at Compaq and Intelligent Electronics. He worked a 12-year stint at IBM, where he held the title of Director of North American Fulfillment at the time of his departure. He earned a bachelor's degree in industrial engineering at Auburn University and later an MBA at Duke University.

Cook was initially charged with wringing out inefficiencies in the company's supply chain. In 2005, he was named the company's Chief Operating Officer.

In a memo to employees, the all-business Cook said that the company's best days lie ahead.

“I want you to be confident that Apple is not going to change. I cherish and celebrate Apple's unique principles and values. Steve built a company and culture that is unlike any other in the world and we are going to stay true to that – it is in our DNA. We are going to continue to make the best products in the world that delight our customers and make our employees incredibly proud of what they do.”

“I love Apple and I am looking forward to diving into my new role,” he added. “I am confident our best years lie ahead of us and that together we will continue to make Apple the magical place that it is.”