The nightjars (family Caprimulgidae) are a family of birds belonging to the order Caprimulgiformes. These nocturnal birds occur in all continents except Antarctica. They are aerial feeders, flying mostly at night to capture preys with their wide mouth flanked by sensitive whisker-like feathers, and spend the day at roost hidden thanks to their cryptic plumages, either on branches or directly on the ground. Some members of this family are unique among birds by undergoing a dormancy period in winter.

The family comprises 98 extant species belonging to 22 genera. Genus Eurostopodus (7 species) has an Australasian distribution. Genus Lyncornis (2 species) is found in the Indomalayan region and genus Gactornis (1 species) is endemic to Madagascar. Genera Lurocalis (2 species), Nyctiprogne (2 species), Nyctipolus (2 species), Nyctidromus (2 species), Tepuiornis (1 species), Uropsalis (2 species), Quechuavis (1 species), Setopagis (3 species), Systellura (1 species), Eleothreptus (2 species), Antiurus (1 species), Hydropsalis (4 species), Siphonorhis (2 species of which 1 probably extinct), Nyctiphrymnus (4 species), Phalaenoptilus (1 species), Antrostomus (12 species) and Chordeiles (6 species) are found in the Neotropics. Genus Veles (1 species) has an Afrotropical distribution. The large genus Caprimulgus (39 species of which 1 disputed) is widespread along the Old World.