Google Delivers Social Graph API

Google has announced a new set of social networking APIs that help people find friends.

Google's new Social Graph API makes information about the public connections between people on the Web easily available and useful, said Brad Fitzpatrick, a software engineer at Google.

The new Google Social Graph API "takes all the existing public relationship data on the Web and makes it easily accessible behind the new API," Fitzpatrick said.

"You can then use the API to do useful things like make the Web more social and make it easier to find friends in new places," he said.

Basically, Fitzpatrick said all of this social information is already out there and no applications are really consuming it. "But with all the social apps getting popular lately, there is demand to access the social graph, and that's why we built the social graph API," he said.

A social graph establishes who an individual is connected to based on the type of connections, such as work, friendship, interests, and location.

With the Social Graph API, developers can now utilize public connections their users have already created in other Web services, Google officials said.

The Google Social Graph API helps index the public Web for XFN (XHTML Friends Network), FOAF (Friend of a Friend) markup and other publicly declared connections.

Yet, the API only uses public data. The API returns Web addresses of public pages and publicly declared connections between them. The API cannot access non-public information, such as private profile pages or Websites accessible to a limited group of friends, Google officials said.

The Google Social Graph API is aimed at programmers who want to access the global, public social graph either from a Web page or from a server. The API returns a JSON (JavaScript Object Notation) data structure in response to a URL.

In a nutshell, Fitzpatrick said with the new API Google crawls the Web to find publicly declared relationships between people's accounts, just like Google crawls the Web for links between pages.

"But instead of returning links to HTML documents, the API returns JSON data structures representing the social relationships we discovered from all the XFN and FOAF," Fitzpatrick said. "When a user signs up for your app, you can use the API to remind them who they've said they're friends with on other sites and ask them if they want to be friends on your new site."

Dion Almaer, another Google software engineer and an expert in Asynchronous JavaScript and API wrote in his blog:

"This is exciting to me as:

• It actually uses the microformat standards such as XFN
• The API is a simple URL, like the Chart Server API. E.g. http://socialgraph.apis.google.com/lookup?q=bradfitz.com&edo=1&pretty=1&callback=onDataLoaded
• Brad uses a resource that others do not have access too…. he uses the Google crawler. Genius!"

Building on its social networking plunge with the Google Open Social initiative, Google now is testing the waters to see how it can help get social data out there and rally around open standards, the company said.