The Social Graph

Mark Zuckerberg, founder of Facebook, used this term "social graph" to explain the way he envisioned Facebook to work. It is loosely described as, "the global mapping of everybody and how they're related. Facebook planned to take advantage of these relationships between people to offer a richer online experience.
This concept of a social graph has greatly changed social media. It allows one to connect through people, places, groups, etc. Not only is this beneficial for an individual for an individual building a network, but also for a business trying to form connections. This connections across this social graph allow organizations to reach a larger audience. For example, not only do they reach an individual, but they are then opened up to that individual's whole network as well. It's like an infinite publicity web for organizations.