Tennis star Serena Williams, actor Dustin Hoffman and author James Patterson are among famous faces who've signed up as instructors for MasterClass, a company that allows people to learn from top professionals through online classes.

Usher and Annie Liebovitz will also debut their classes online in the next few months. Hoffman said 'We're students. The first year. The first five years, the first ten years. We're students after 50 years. I never like to give advice, but I wanted to teach what I wish someone had taught me', while Williams commented 'I wanted to make my class feel as though you're right there on the court with me'.