The Facebook Graph Go library created by Huan Du supports the API with file upload, batch request, FQL and multi-FQL. This library can also be used in Google App Engine. Developer provides usage with quick start and guides for user object, valid access token, graph search, JSON response, batch request, and multi-query procedures.
As a developer, you can figure out how to make your program connect to Facebook, Twitter, SMS, and Email. Or you can use the Embarke API and connect just to Embarke, a messaging platform that connects you to them all. You can skip learning the specifics of how to connect to each of them. The REST API's website has a five minute tutorial video on how to use this gateway to its developer tools for social communications.
In the beginning, there was the Google (SOAP) Search API. In December 2006, Google no longer issued any new keys for this API. Those with keys already could still use the API, but it was effectively deprecated.