Binomial nomenclature is a system of classification introduced by Carolus Linnaeus, the 18th century Swedish naturalist, in which each species is given two names. The first is the generic name, written with a capital letter, which designates the genus to which the species belong and the second is the specific name, indicating the species. The specific name can be single or compound. Usually it begins with a small letter. Capital letter is used, occasionally when the name of species is based after a place or person.