San Francisco-headquartered online courses providing platform Udemy has raised $50 million from a single investor, Japan-based educational publisher Benesse Holdings. The investment was made at a $2 billion pre-money valuation, the company said. Udemy which offers online learning courses from business analytics to ukulele lessons was founded in 2010 by Gagan Biyani, Oktay Caglar and Eren Bali.