Playfair may refer to: Playfair (surname) Playfair (lunar crater) Playfair (Martian crater) PlayFair, software that removes Apple's FairPlay DRM file encryption, now succeeded by Hymn See also Playfair Project TS Playfair, a Canadian sail training vessel Playfair's axiom named after John Playfair Playfair cipher, a manual encryption technique invented in 1854 by Charles Wheatstone Playfair Cricket Annual Playfair Race Course Lyon Playfair Library, now known as the Central Library, at Imperial College London