Santa Claus is a mythical gift-giving figure in various cultures who distributes presents to children, traditionally on December 24, Christmas Eve. The popular American form Santa Claus originated as a mispronunciation of Dutch Sinterklaas which is a contracted form of Sint Nicolaas (Saint Nicholas).

Father Christmas is a well-loved figure in many countries and predates the "Santa Claus" character. "Father Christmas" is similar in many ways, though the two have quite different origins. Using 'Santa' in places that predominantly call him 'Father Christmas' is often viewed as an Americanism and is quite rare, although they are generally regarded as the same character. Father Christmas is also present instead of "Santa" in Albania ("Babadimri"), Armenia ("Gaghant Baba"), Denmark ("Julemanden"), Hungary ("Mikulás"), Italy ("Babbo Natale"), Lithuania ("Kalėdų Senelis"), Brazil ("Papai Noel"), Portugal ("Pai Natal"), Romania ("Moş Crăciun"), Russia (Ded Moroz ), Germany ("Weihnachtsmann" or "Nikolaus"), Scottish Highlands ("Daidaín na Nollaig"), France and French Canada ("Le Père Noël"), Ireland ("Daidí na Nollaig"), Finland ("Joulupukki"), Norway ("Julenissen"), Sweden ("Jultomten"), Bulgaria ("Dyado Koleda"), Turkey ("Noel Baba"), Serbia and Bosnia and Herzegovina ("Deda Mraz"), Spain and Spanish-speaking Latin America ("Papá Noel"), Afghanistan ("Baba Chaghaloo"), Iraq and South Africa ("Vader Kersfees"), Chile (Viejo Pascuero), Malta ("San Niklaw"), Egypt ("Papa Noël"), Iran ("Baba Noel").

Santa Claus, legendary bringer of gifts at Christmas is generally depicted as a fat, jolly man with a white beard, dressed in a red suit trimmed with white, and driving a sleigh full of toys drawn through the air by eight reindeer. Santa (also called Saint Nicholas and Saint Nick) is said to visit on Christmas Eve, entering houses through the chimney to leave presents under the Christmas tree and in the stockings of all good children.

The historical Saint Nicholas was venerated in early Christian legend for saving storm-tossed sailors, defending young children, and giving generous gifts to the poor. Although many of the stories about Saint Nicholas are of doubtful authenticity , his legend spread throughout Europe, emphasizing his role as a traditional bringer of gifts. The Christian figure of Saint Nicholas replaced or incorporated various pagan gift-giving figures such as the Roman Befana and the Germanic Berchta and Knecht Ruprecht.

In these countries Nicholas was sometimes said to ride through the sky on a horse. He was depicted wearing a bishop's robes and was said to be accompanied at times by Black Peter, an elf whose job was to whip the naughty children. The feast day of Nicholas, when presents were received, was traditionally observed on December 6. After the Reformation, German Protestants encouraged veneration of the (Christ child) as a gift giver on his own feast day, December 25. When the Nicholas tradition prevailed, it became attached to Christmas itself.

The American version of the Santa Claus figure received its inspiration and its name from the Dutch legend of Sinter Klaas, brought by settlers to New York in the 17th century. As early as 1773 the name appeared in the American press as St. A Claus, but it was the popular author Washington Irving who gave Americans their first detailed information about the Dutch version of Saint Nicholas.

The fully detailed modern image of Santa Claus plays a part in Christmas celebrations around the world. People are reminded of Santa Claus through advertising, greeting cards, decorations, and the annual appearance of Santas in department stores and shopping malls ,in some cases accompanied by Mrs. Claus and Santa's elves. The figure of Santa Claus occurs in motion pictures and in songs such as Santa Claus Is Coming to Town, and Here Comes Santa Claus. Children write letters to Santa Claus and set out milk and cookies on Christmas Eve as a snack for Santa.

Although most adults view Santa as the embodiment of a spirit of giving, some argue that the modern image of Santa Claus conflicts with the true meaning of Christmas and promotes greed and commercialism. To reconcile the legend of Santa Claus with the religious significance of Christmas, some Christians emphasize that the modern figure is derived from legends about a saint who symbolized love, caring, and generosity.