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The swallows and martins are a group of passerine birds in the family Hirundinidae which are characterised by their adaptation to aerial feeding. Swallow is used colloquially in Europe as a synonym for the Barn Swallow.
Within the swallow, the name "martin" tends to be used for the squarer-tailed species, and the name "swallow" for the more fork-tailed species; however, there is no scientific distinction between these two groups. The family contains around 83 species in 19 genera.