OpenSocial

Source: https://en.wikipedia.org/wiki/OpenSocial

Official Website: https://www.opensocial.org

OpenSocial is a set of common application programming interfaces (APIs) for web-based social network applications, developed by Google along with MySpace and a number of other social networks. It was released November 1, 2007. Applications implementing the OpenSocial APIs will be interoperable with any social network system that supports them, including features on sites such as Hi5.com, MySpace, orkut, Netlog, Sonico.com, Friendster, Ning and Yahoo!.