William "Bud" Abbott (October 2, 1895 - April 24, 1974) and Lou Costello (March 6, 1906 - March 3, 1959) were an American comedy duo whose work on stage, radio, film, and television made them the most popular comedy team during the 1940s and 1950s. Their "Who's on First" sketch is considered one of the greatest comedy routines of all time.

They were spoofed by Bud the Snake and Lou the Spider (who were also named after them) in the Chip 'n Dale Rescue Rangers episode, "Good Times, Bat Times" and also made a cameo appearance on Weebo's video screen in Flubber. Abbot Costello from Adventures of the Gummi Bears is even named after them.