Bird Classification (linked with wikipedia)

Kingdom : Animal	Phylum : Chordata	Class : Aves
Subclass: Neornithes (29 orders of modern birds)	Superorder: Palaeognathae Struthioniformes (ratites)  • Tinamiformes (tinamous) Superorder: Neognathae Accipitriformes (eagles and relatives) • Anseriformes (waterfowl)  • Apodiformes (swifts and hummingbirds)  • Caprimulgiformes (nightjars and relatives)  • Cariamae (seriemas and relatives)  • Charadriiformes (gulls and relatives)  • Ciconiiformes (storks)  • Coliiformes (mousebirds)  • Columbiformes (doves and pigeons)  • Coraciiformes (kingfishers and relatives)  • Cuculiformes (cuckoos and relatives)  • Falconiformes (falcons and relatives)  • Galliformes (gamebirds)  • Gaviiformes (loons or divers)  • Gruiformes (cranes and relatives)  • Passeriformes (perching birds)  • Pelecaniformes (pelicans and relatives)  • Phaethontiformes (tropicbirds)  • Phoenicopteriformes (flamingos)  • Piciformes (woodpeckers and relatives)  • Podicipediformes (grebes)  • Procellariiformes (albatrosses and petrels)  • Psittaciformes (parrots)  • Pteroclidiformes (sandgrouses)  • Sphenisciformes (penguins)  • Strigiformes (owls)  • Trogoniformes (trogons and quetzals)
Fossil birds	Archaeopteryx • Enantiornithes • Hesperornithes

Classified
Scientists place birds in the branch, or phylum, of the animal kingdom called Chordata, meaning animals with backbones. The Chordata are divided into classes. Birds belong to the class Aves. This class in turn is divided into two subclasses, and they in turn are divided into a number of orders. there are nearly 29 orders.  Scientific study of bird called Ornithology