In traditional festive legend, Santa Claus's reindeer pull a sleigh through the night sky to help Santa Claus deliver gifts to children on Christmas Eve. The commonly cited names of the eight reindeer are Dasher, Dancer, Prancer, Vixen, Comet, Cupid, Donner and Blitzen. They are based on those used in the 1823 poem "A Visit from St. Nicholas" (commonly called "The Night Before Christmas") by Clement Clarke Moore, arguably the basis of the reindeers' popularity.

The enduring popularity of the Christmas song "Rudolph the Red-Nosed Reindeer" has led to Rudolph often joining the list, bringing the number of Santa Claus's reindeer up to nine.

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