Friend of a friend

Friend of a friend (FOAF) is a phrase used to refer to someone that one does not know well, literally, a friend of a friend.

In some social sciences, the phrase is used as a half-joking shorthand for the fact that much of the information on which people act comes from distant sources (as in "It happened to a friend of a friend of mine") and cannot be confirmed. It is probably best known from urban legend studies, where it was popularized by Jan Harold Brunvand.

The acronym FOAF was coined by Rodney Dale and used in his 1978 book The Tumour in the Whale: A Collection of Modern Myths.

The rise of social network services has led to increased use of this term. Six degrees of separation is a related theory.

Bo Anderson made an analysis of the friend-of-a-friend relationship in connection with his criticism of balance theory.

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