Birds are feathered vertebrates of the class Aves, most of which are capable of flight and have an active metabolism and all of which have beaks, no teeth, and lay eggs. Although birds evolved from a common ancestor, there are around 30 orders of birds, around 180 families, around 2000 genera, and about 10,000 bird species. The most efficient way to type the bird species is by the orders they belong to.
The order Anseriformes, which includes ducks, geese, swans, and their relatives, has 161 bird species. Members of this order are found in every part of the world except the Antarctic. The order Galliformes includes a number of game birds, including guineafowl, pheasants, quails, turkeys, grouse, and partridges. This order has over 250 bird species.
The order Caprimulgiformes consists of birds collectively called nightbirds. These include the oddly named nightjars and frogmouths. The order Apodiformes consists of hummingbirds, with 328 species, and swifts.
The order Balaenicipitiformes has shoebill or whale-headed storks, while Ciconiiformes has other storks and related birds, such as herons, ibises, and spoonbills, and Charadriiformes includes other shorebirds, such as puffins, lapwings, plovers, gulls, terns, sandpipers, and snipe. The order Coliiformes only includes mousebirds, but Columbiformes contains doves, pigeons, and dodos.
Kingfishers, hornbills, bee-eaters, hoopoes are in the order Coraciiformes, while cuckoos and roadrunners and their relatives are members of the order Cuculiformes. The order Falconiformes is characterized as containing diurnal birds of prey, and these include eagles, hawks, kites, vultures, condors, and falcons. There are 233 species of eagles, hawks, and their relatives alone, while in contrast, the order Gaviiformes has five species of loon, and that is all.
The order Galbuliformes has puffbirds and jacamars, and the order Gruiformes consists of coots, cranes, and rails. The order Mesitornithiformes has the mesites, Musophagiformes has the turacos, and Opisthocomiformes has the hoatzin. The order of perching birds, Passeriformes, has 95 families, and includes thrushes, swallows, crows, jays, flycatchers, orioles, birds-of-paradise, fantails, vireos, honeyeaters, lyrebirds, waxwings, mockingbirds, nuthatches, starlings, wrens, cardinals, grosbeaks, sparrows, buntings, finches, tanagers, blackbirds, larks, chickadees, and titmice.
There are six families and 67 bird species in the order Pelecaniformes, including pelicans, anhingas, cormorants, frigates, and boobies. The order Phoenicopteriformes, another small order, has the five species of flamingos. Woodpeckers, honeyguides, and toucans are members of the order Piciformes, and the 22 species of grebes are members of the order Podicipediformes.
Albatrosses and petrels, classified as tub-nosed seabirds are members of the order Procellariiformes, while parrots, cockatoos, parakeets, lorikeets, lories, and their relatives are members of the order Psittaciformes. The seventeen species of penguin are members of the order Sphenisciformes, and the over 200 species of owls belong to the order Strigiformes.
The trogons belong to the order Trogoniformes. The buttonquail belongs to the order Turniciformes, and paleognath birds — such as cassowaries, emus, rheas, ostriches, and kiwis — belong to the order Sturthioniformes. The tinamous belongs to the order Tinamiformes.