African and Indian elephants are separate species, Loxodonta africana and Elephas maximus. The African elephant has two populations, savannah and forest, and recent genetic studies have led to a classification of these as separate species, Loxodonta cyclotis. (See http://www.education.guardian.co.uk/Print/0,3858,4244642,00.html) This work has important implications for conservation, because it means there are two species that need protection, and fewer of each species. There's also a potential danger in that the forest elephant isn't explicitly listed as an endangered species, and poachers and smugglers might thus be able to evade the law forbidding trade in endangered animals and their body parts.
Elephants have been used in various capacities by humans. In Siam and India they were used in the military, and have been used for transportation and entertainment, as in American circuses. The Carthaginian general Hannibal attempted to take elephants across the Alps when he was fighting the Romans, with little success. However, elephants have never been truly domesticated: the male elephant in heat is dangerous and difficult to control, such that elephants used by humans have typically been female.
In the wild, elephants exhibit complex social behavior and strong family bonds.
Public domain picture from U.S. Fish and Wildlife Service
See also: Proboscidea