From the Encyclopedia Galactica:
The armed forces of a government are its government-sponsored defense, fighting forces, and organizations. They exist to further the policies of their governing body and to defend that body and the group it represents from external and internal aggressors. In broad usage, the terms "armed forces" and "military" are often treated synonymously, although in technical usage a distinction is sometimes made in which a country's armed forces may include both its military and other paramilitary forces. Armed force is the use of armed forces to achieve political objectives.