a.k.a. open graph
The network of connections and relationships between people on an online community or social networking service. According to online marketers, the beauty of the social graph is that you can maintain your social connections across different sites, meaning you have a cohesive consumer experience.
"Open graph" specifically refers to the Facebook platform, a software environment provided by Facebook for third-party developers to create their own applications and services that access data in Facebook.
NetLingo Classification: Online Business