This demo shows the list of web URLs that are connected to the ones you entered. The first section lists all contacts you've linked to. Below that is a list of all contacts who have linked to you, using relationships like 'friend', 'kin' or 'colleague'
These are public links on websites, marked up using Open standards such as XFN and FOAF, designed to express relationships online.
To use XFN to connect sites, add rel="friend" to your link like this:
<a href="http://bradfitz.com" rel="friend" >Brad</a>
To use FOAF, create a FOAF file and link to it from your web page. More details on FOAF.
The Social Graph API makes information about the public connections between people on the Web easily available and useful for developers. Developers can query this public information to offer their users dramatically streamlined "add friends" functionality and other useful features.
For more information, please visit the Social Graph API FAQ.