In the United States, a county is a political and geographic subdivision of a state, usually assigned some governmental authority. The term "county" is used in 48 of the 50 U.S. states. The exceptions are Louisiana and Alaska, where the functionally equivalent subdivisions are called, respectively, parishes and boroughs. Numerous consolidated city–counties exist throughout the U.S. in which a city has merged with its county to form one unified jurisdiction with the governmental powers of both entities.