Although the question isn't as specific as I would personally like it to be, I believe you are speaking of the classification system for living organisms: Kingdom, Phylum, Class, Order, Family, Genus, Species.
[[User:71.186.203.237|71.186.203.237]] 15:31, 7 Jun 2008 (UTC)~
For example, all birds are in the Animalia Kingdom, Phylum of Chordata (with a backbone), and Class Aves (birds). At the Order level, the birds begin to diverge. For instance, the pelicans are in the Pelecaniformes Order while the nuthatches are in the Passeriformes Order. Next comes the Family with the pelicans in the Pelecanidae family and the nuthatches in the Sittidae family. At the genus level, the nuthatches are in the genus Sitta. At the species level, there are the White-breasted Nuthatch (Sitta carolinensis), Red-breasted Nuthatch (Sitta canadensis), Brown-headed Nuthatch (Sitta pusilla) and Pygmy Nuthatch (Sitta pygmaea). The scientific names are all in Latin so that scientists around the world can communicate in a common language. A White-breasted Nuthatch can then be classified as: Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Sittidae
Genus: Sitta
Species: carolinensis