Military reserve force

A military reserve force is a military organization composed of citizens of a country who combine a military role or career with a civilian career. They are not normally kept under arms and their main role is to be available to fight when a nation mobilizes for total war or to defend against invasion. Reserve forces are generally not considered part of a permanent standing body of armed forces. The existence of reserve forces allows a nation to reduce its peacetime military expenditures while maintaining a force prepared for war. It is analogous to the historical model of military recruitment before the era of standing armies.

In some countries, such as the United States, Spain and the United Kingdom, members of the reserve forces are civilians who maintain military skills by training, typically one weekend a month. They may do so as individuals or as members of standing reserve regiments, for example the Territorial Army of the United Kingdom. In some cases a militia, home guard,or state guard could constitute part of a military reserve forces, such as the United States National Guard, State Defense Forces, Home Guard of Norway, Home Guard of Sweden, or Home Guard of Denmark.