The swallows, martins and saw-wings, or Hirundinidae, are a family of passerine birds found around the world on all continents, including occasionally in Antarctica. Highly adapted to aerial feeding, they have a distinctive appearance. The term Swallow is used colloquially in Europe as a synonym for the barn swallow.

Swallows are able to produce many different calls or songs, which are used to express excitement, to communicate with others of the same species, during courtship, or as an alarm when a predator is in the area. The songs of males are related to the body condition of the bird and are presumably used by females to judge the physical condition and suitability for mating of males. Begging calls are used by the young when soliciting food from their parents. The typical song of swallows is a simple, sometimes musical twittering.

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