"The strength of the nation's Armed Forces, including the reserve components, has historically been an area of keen interest to Congress. The increasing use of the reserves since the end of the Cold War has led to greater congressional interest in various issues that bear on the vitality of the reserve components, such as funding, equipment, and personnel policy. This report is designed to provide an overview of key reserve component personnel issues. The term 'Reserve Component' refers collectively to the seven individual reserve components of the Armed Forces: the Army National Guard of the United States, the Army Reserve, the Navy Reserve, the Marine Corps Reserve, the Air National Guard of the United States, the Air Force Reserve, and the Coast Guard Reserve. The purpose of these seven reserve components, as codified in law at 10 U.S.C. 10102, is to 'provide trained units and qualified persons available for active duty in the armed forces, in time of war or national emergency, and at such other times as the national security may require, to fill the needs of the armed forces whenever more units and persons are needed than are in the regular components.'"
CRS Report for Congress, RL30802
Federation of American Scientists: http://fas.org/