Annual training refers to the yearly training period conducted by all National Guard and Reserve

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...

 components of the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 military

Military

A military is an organization authorized by its greater society to use lethal force, usually including use of weapons, in defending its country by combating actual or perceived threats. The military may have additional functions of use to its greater society, such as advancing a political agenda e.g...

. Usually advertised as two weeks each year that personnel must attend, annual training periods have increased to as much as month-long events during the Iraq War. This training may be conducted at the home unit or at a NTC (national training center)