Google has released a set of open application programming interfaces (APIs) that lets developers craft applications for multiple social networks at once.

Dubbed OpenSocial, the APIs will work with any participating social network. The APIs allow applications to integrate information from the user's profile, data about their online friends or contacts and activities.

A programmer could use the information to build a messaging application that allows them to exchange instant messages with friends in their network, and potentially across networks.

Currently an application developed for Facebook is limited to that one service. A set of common, broadly supported APIs will allow developers to distribute their applications across multiple social services.

Facebook was the first major social network to open up its platform to developers. The service has attracted more than 5,000 applications since it opened its APIs last June.

Google however is going beyond building an open alternative to Facebooks APIs. OpenSocial also boast support from enterprise players Salesforce.com and Oracle.

Early OpenSocial supporters include LinkedIn, Friendster and Plaxo, as well as the Google owned Orkut social network. Big networks such as Myspace and Facebook are missing from the list of partners.

Google has an advertising partnership with Myspace. Facebook last week signed a similar deal with Microsoft, which is believed to have outbid Google for the agreement.