Best friends forever

A large survey of friendship in the UK in 2003 found that on average, people had nine close friends.

[7] Barbara Delinsky described a BFF as "someone you don't have to see every day to still connect with, someone who loves you whether you talk often or not, someone who would drop everything and catch the next flight if you needed her.

"[9] In a study conducted at the University of Oxford, Tamas David-Barrett and his colleagues reported that there is an unusually large number of profile pictures on Facebook that depict two women.

After eliminating the alternative hypotheses, the study concluded that the finding suggests that (a) close friendship formation patterns are universal among humans, and (b) there is a marked gender difference in the propensity to form lasting friendship due to an evolutionary ultimate cause.

[10] This suggests that the BFF concept, albeit with a different name, may exist in many cultures, going back to evolutionary times.