Facebook founder Mark Zuckerberg features in a long line of university dropouts who became millionaires after founding technology companies - Bill Gates and Steve Jobs among them.

But 12 years after leaving Harvard to work on Facebook full time, he has returned to pick up his degree.

Zuckerberg founded what was then called "The Facebook" in his college dormitory in 2004. The service was at first limited only to Harvard students before expanding to other Ivy League universities.

He is due to deliver the university's commencement address, a speech given to graduating students, later on Thursday. After receiving the honour he posted a photo of him with his parents Edward and Karen Zuckerberg.