Google, Inc. has announced the release of OpenSocial, a set of common APIs for building social applications across the web, for developers of social applications and for websites that want to add social features.

The company says OpenSocial will unleash more powerful and pervasive social capabilities for the web, empowering developers to build far-reaching applications that users can enjoy regardless of the websites, web applications, or social networks they use.

The release of OpenSocial marks the first time that multiple social networks have been made accessible under a common API to make development and distribution easier and more efficient for developers.

The proliferation of unique APIs across dozens of social websites is forcing developers to choose which ones to write applications for and then spend their time writing separately for each. OpenSocial gives developers of social applications a single set of APIs to learn for their applications to run on any OpenSocial-enabled website.

Google points out that one of the most important benefits of OpenSocial is the vast distribution network that developers will have for their applications. The sites that have already committed to supporting OpenSocial -- Bebo, Engage.com, Friendster, hi5, Hyves, imeem, LinkedIn, mixi, MySpace, Ning, Oracle, orkut, Plaxo, Salesforce.com, Six Apart, Tianji, Viadeo, and XING -- represent an audience of about 200 million users globally.

Critical for time- and resource-strapped developers is being able to “learn once, write anywhere” -- learn the OpenSocial APIs once and then build applications that work with any OpenSocial-enabled websites.

Several developers, including Flixster, FotoFlexer, iLike, RockYou, Slide, Theikos, and VirtualTourist have already built applications that use the OpenSocial APIs. A developer sandbox will be available soon at http://sandbox.orkut.com so developers can go in and start testing the OpenSocial APIs. The goal is to have developers build applications in the sandbox so they can deploy on orkut and ultimately other OpenSocial sites.

The common method that OpenSocial provides for writing social applications means that websites can engage a much larger pool of third-party developers than they could otherwise. They can direct resources that might have gone to maintaining a proprietary API and supporting its developer community to other projects.

The OpenSocial APIs give developers (with users' permission) access to the data needed to build social applications: access to an application user's profile information, their list of friends, and the ability to share their activities with friends.

Developers will have access to:

- Three JavaScript and Gdata APIs to access social functions
- A live developer sandbox on orkut at sandbox.orkut.com
- Sample code, documentation, and a support group available at code.google.com

Websites will have access to:

- A tool to help OpenSocial-enable their websites
- A support forum for communicating with Google and other websites
- Sample code, documentation, and a support group available at code.google.com