maratd's comment next to yours is correct. It's actually an old term (well, old relative to social media) used by psychologists to describe the way people make

maratd's comment next to yours is correct. It's actually an old term (well, old relative to social media) used by psychologists to describe the way people make judgments (consciously or otherwise) based on the behavior of their peers. http://en.wikipedia.org/wiki/Social_proof http://en.wikipedia.org/wiki/Social_proof