They inspired a boom in self-publishing with Blogger, then turned the world to 140 characters with Twitter. Now Ev Williams and Biz Stone have launched two new websites – Medium and Branch – in what they hope will prompt an "evolutionary leap" in online sharing.
Williams and Stone are still directors of Twitter, but are involved in the new ventures through their San Francisco-based incubator fund, The Obvious Corporation.
Like Twitter, both Medium and Branch are publishing platforms where users can share pictures, articles and text. And both are more or less splinter services to Twitter.
But what are Medium and Branch?