Dropbox founder Drew Houston explains his success
1 July 2014 Last updated at 00:17 BST
Drew Houston founded online file-sharing service Dropbox seven years ago. The firm is now estimated to be worth about $10bn (£5.9bn).
But it was not an overnight success, and he had several failed ventures along the way.
Mr Houston explains how he came up with the idea for the firm and the factors which, he believes, have made it work.