What Is the Fastest Thing in the World? is a Greek fairy tale collected by in Folktales of Greece. It is Aarne-Thompson type 875 and has many Greek and Slavic variants, generally revolving about the exchange of clever answers. This type of tale is the commonest European tale dealing with witty exchanges. In ballad form, the clever answers to the riddles, and the winning of a husband by them, are found in Child ballad 1, Riddles Wisely Expounded.