OpenSocial is a public specification that defines a component hosting environment (container) and a set of common APIs for web-based applications
OpenSocial
OpenSocial is a public specification that defines a component hosting environment (container) and a set of common application programming interfaces (APIs) for web-based applications. Initially it was designed for social network applications and was developed by Google along with MySpace and a number of other social networks. In more recent times it has become adopted as a general use runtime environment for allowing untrusted and partially trusted components from third parties to run in an existing web application. The OpenSocial Foundation has also moved to integrate or support numerous other open web technologies. This includes Oauth and OAuth 2.0, Activity Streams, and portable contacts, among others.
Structure
Based on HTML and JavaScript, as well as the Google Gadgets framework, OpenSocial includes multiple APIs for social software applications to access data and core functions on participating social networks.[6] Each API addresses a different aspect:.[7] It also includes APIs for contacting arbitrary third party services on the web using a proxy system and OAuth for security.
In version 0.9 OpenSocial added support for a tag-based language.This language is referred to as OSML and allows tag-based access to data from the OpenSocial APIs that previously required an asynchronous client side request. It also defined a rich tag template system and adopted an expression language loosely based on the Java Expression Language. Starting in version 2.0 OpenSocial adopted support for Activity Streams format