Which comedy duo made the skit "Who's on First" famous?

"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'").

The names of the players in the skit are Who's on first, What's on second, I don't know is on third, Why is the left fielder, Because is the center fielder, I don"t give a darn is the short stop, catcher is named Today, and Tomorrow is the name of the pitcher. In 1999 Time magazine named "Who's on First" the best comedy sketch of the 20th century. In 2005 the line "Who's on First" was included on the American Film Institute's list of 100 memorable movie quotations.