|Initial release||June 2007|
|Stable release||2.0.1 / November 16, 2011|
|Type||Web application framework|
|License||Apache License 2.0|
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.
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 
|0.5||June 15, 2007|
|0.6||December 21, 2007|
|0.7||February 4, 2008|
|0.8||May 28, 2008|
|0.9||April 16, 2009|
|1.0||March 15, 2010|
|1.1||November 18, 2010|
|2.0||August 18, 2011|
|2.0.1||November 23, 2011|
OpenSocial was rumored to be part of a larger social networking initiative by Google code-named "Maka-Maka", which is defined as meaning "intimate friend with whom one is on terms of receiving and giving freely" in Hawaiian.
Initial OpenSocial support experienced vulnerabilities in security, with a self-described amateur developer demonstrating exploits of the RockYou gadget on Plaxo, and of Ning social networks using the iLike gadget.
An open source project, Shindig, was launched in December, 2007, to provide a reference implementation of the OpenSocial standards. It has the support of Google, Ning, and other companies developing OpenSocial-related software. The Myspace OpenSocial parser was released as project Negroni in January, 2011 and provides a C# based implementation of OpenSocial.
Criticism of Initial Release 
Opened to much fanfare in news coverage, OpenSocial did not work well in the beginning; it only ran on Google-owned Orkut, and only with a limited number of gadgets, returning errors for other gadgets. Other networks were still looking into implementing the framework.
As reported by TechCrunch on November 5, 2007, OpenSocial was also quickly cracked. The total time to crack the OpenSocial-based iLike on Ning was just 20 minutes, according to TechCrunch, with the attacker being able to add and remove songs on a user's playlist, and to look into information on their friends.
On December 6, TechCrunch followed up with a report by MediaPops founder Russ Whitman, who said "While we were initially very excited, we have learned the hard way just how limited the release truly is." Russ added that "core functionality components" are missing and that "write once, distribute broadly" was not accurate.
While OpenSocial has seen a decline in popularity among social networks, it is seeing wider adoption in enterprise companies in recent years as a plugable extension mechanism for web products. Two of the leading vendors in enterprise social networks, IBM and Jive Software, based their apps strategy on OpenSocial.
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- "OpenSocket on Facebook | Facebook". Apps.facebook.com. Retrieved 2013-01-11.
- "OpenSocket". OpenSocket. Retrieved 2013-01-11.
- [dead link]