Hummingbird
A variety of hummingbirds from Ernst Haeckel's 1904 Kunstformen der Natur (Artforms of Nature)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Trochiliformes or Apodiformes
Family:	Trochilidae Vigors, 1825

Hummingbirds are small birds of the family Trochilidae.

They are among the smallest of birds: most species measure 7.5–13 cm (3–5 in). The smallest living bird species is the 2–5 cm Bee Hummingbird. They can hover in mid-air by rapidly flapping their wings 12–80 times per second (depending on the species). They are also the only group of birds able to fly backwards. Their rapid wing beats do actually hum. They can fly at speeds over 15 m/s (54 km/h, 34 mi/h).