The swallows and martins are a group of passerine birds in the family Hirundinidae which are characterised by their adaptation to aerial feeding.
Like the unrelated swifts and nightjars, which hunt in a similar way, they have short bills, but strong jaws and a wide gape.
The legs are short, and their feet are adapted for perching rather than walking. Swallows are capable of walking and even running, but they do so with a shuffling, waddling gait.
The most common plumage is glossy dark blue or green above and plain or streaked underparts, often white or rufous. Species which burrow or live in dry or mountainous areas are often matte brown above.
Swallows are excellent fliers, and use these skills to attract a mate and to feed.