Evan Williams, Twitter Co-founder

Evan Williams is behind the internet service Twitter. It invites people to share their thoughts in 140 characters or less.

Luckily on The Interview Carrie Gracie has a little longer to find out Evan's plans for the free exchange of information.

She asks him about how he went from a farm in Nebraska to being a big player in Silicon Valley, how he thinks Twitter can be a force for good and whether he will sell at any price?