Scientifically, birds are a group of warm-blooded vertebrates constituting the class Aves (/ˈeɪviːz/), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds are feathered theropod dinosaurs and constitute the only known living dinosaurs. Likewise, birds are considered reptiles in the modern cladistic sense of the term, and their closest living relatives are the crocodilians. Birds are descendants of the primitive avialans (whose members include Archaeopteryx) which first appeared during the Late Jurassic.

This site deals only with edible birds and those birds that commonly form a part of the human diet, of which chickens form the major constituents (in culinary usage, birds are birds (aves), poultry and fowl) chickens' ancestors, junglefowl are also game animals). Pigeons, interestingly are one of the earliest species domesticated by humans and are both farmed (poultry) as well as being hunted in the wild (game). Turkeys, are game birds in the wild, poultry when farmed and also are fowl as they are related to chickens.

Birds are important not just for their meat, but also because several species (most notably chickens, ducks and quail) are reared for their eggs.