For example, in the image below, Brad just joined Twitter but has no friends on it. Using the Social Graph API, Twitter could provide Brad a way to find out that his friend Jane is also on Twitter. Here’s how: Brad has linked to his homepage (b3) from his Twitter profile (b1) and also from his homepage (b3) to his LiveJournal blog, Bradfitz (b2). On LiveJournal, Brad is friends with Jane274 (j2), but Brad doesn’t know that Jane274 (j2) also has a Twitter profile (j1). Since the Social Graph API has indexed that Brad and Jane already have declared a public friendship on LiveJournal, it can let Brad know that he might want to add Jane (j1) on Twitter as well.