Who's on First?

"Who's on First?" is a comedy routine made famous by Abbott and Costello. The premise of the sketch is that Abbott is identifying the players on a baseball team for Costello, but their names and nicknames can be interpreted as non-responsive answers to Costello's questions. For example, the first baseman is named "Who"; thus, the utterance "Who's on first" is ambiguous between the question ("Which person is the first baseman?") and the answer ("The name of the first baseman is 'Who'").

"Who's on First?" is descended from turn-of-the-century burlesque sketches that used plays on words and names. Examples are "The Baker Scene" (the shop is located on Watt Street) and "Who Dyed" (the owner is named "Who"). In the 1930 movie Cracked Nuts, comedians Bert Wheeler and Robert Woolsey examine a map of a mythical kingdom with dialogue like this: "What is next to Which." "What is the name of the town next to Which?" "Yes." In English music halls (England's equivalent of vaudeville theatres), comedian Will Hay performed a routine in the early 1930s (and possibly earlier) as a schoolmaster interviewing a schoolboy named Howe who came from Ware but now lives in Wye. By the early 1930s, a "Baseball Routine" had become a standard bit for burlesque comics across the United States. Abbott's wife recalled him performing the routine with another comedian before teaming with Costello.

Bud Abbott stated that it was taken from an older routine called "Who's The Boss?", a performance of which can be heard in an episode of the radio comedy program It Pays to Be Ignorant from the 1940s. After they formally teamed up in burlesque in 1936, he and Costello continued to hone the sketch. It was a big hit in 1937, when they performed the routine in a touring vaudeville revue called "Hollywood Bandwagon".

In February 1938, Abbott and Costello joined the cast of The Kate Smith Hour radio program, and the sketch was first performed for a national radio audience that March. The routine may have been further polished before this broadcast by burlesque producer John Grant, who became the team's writer, and Will Glickman, a staff writer on the radio show. Glickman may have added the nicknames of then-contemporary baseball players like Dizzy and Daffy Dean to set up the routine's premise. This version, with extensive wordplay based on the fact that most of the fictional baseball team's players had "strange nicknames" that seemed to be questions, became known as "Who's on First?" Some versions continue with references to Enos Slaughter, which Costello misunderstands as "He knows" Slaughter. By 1944, Abbott and Costello had the routine copyrighted.

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