Most countries have armed forces, which are usually called regular army. Very often, the constitution of a country talks about this army. This is different from rebel groups or militia, who may also train forces. The regular army is a official army of a official country. They are temporary army's. Still, the person in charge of the army is the president or King or the head of the government. Very often, a regular army has two parts:
- Most of the army, are people under arms, even in peace time.
- Part of the army are people who can be called to arms, on request (for example, in case of a conflict)