Caliphs (Arabic: خليفة) are Islamic political leaders succeeding Muhammad.
Caliph, in Arabic, means "successor" or "steward." In the Koran, it is refered to humans as the "stewards" of the Earth. This term has come to mean "successor" of Muhammad. The title of Caliph has been adopted by various Muslim rulers throughout history and is still used by some small Islamic denominations.