Github - publishing source code online
GitHub is a web-based hosting service for software development projects that use the Git revision control system. GitHub offers both commercial plans and free accounts for open source projects. According to the Git User's Survey in 2009, GitHub is the most popular Git hosting site.
The site provides social networking functionality such as feeds, followers and the network graph to display how developers work on their versions of a repository. GitHub also operates a pastebin-style site called Gist, wikis for individual repositories, and web pages that can be edited through a git repository. As of January 2010, GitHub is operated under the name GitHub, Inc.
The software that runs GitHub was written using Ruby on Rails and Erlang by GitHub, Inc. (previously known as Logical Awesome) developers Chris Wanstrath, PJ Hyett, and Tom Preston-Werner.