Launched in 2008 by Tom Preston-Werner, Chris Wanstrath and PJ Hyett, GitHub is a web-based hosting service for software development projects that use the Git revision control system.
GitHub provides paid plans for private repositories and free accounts for open source projects. The site allows users to participate in conversations and discuss, manage or review code, making it easy to share code with friends or strangers, revise projects, and edit work among co-workers.
Though GitHub is used primarily for code, it is also useful for non-code files like Final Cut or Word documents. In addition, GitHub offers social networking functions like feeds, followers, wikis and the social network graph to display how developers work on their versions of a repository.
GitHub’s other services include Gist, a pastebin-style site that provides wikis for individual repositories and web pages, and Speaker Deck, a slide-hosting service. As of December 2013, GitHub reached 10 million repositories.