The Army National Guard (ARNG), in conjunction with the Air National Guard, is an organized militia force and a federal military reserve force of the United States Army. They are simultaneously part of two different organizations: the ARNG of each state, most territories, and the District of Columbia, as well as the federal ARNG. The ARNG is divided into subordinate units stationed in each U.S. region, operating under their respective governors and governor-equivalents.