A Command Post is a term, of military origin, referring to a field location from where the person in charge of a situation issues orders. Command posts are typically temporary and are located to allow maximum access to the site or battlefield, with a minimum of risk to the person in charge.
Most military formations (e.g. an infantry battalion of 800 soldiers) will have 2 command posts. The actual one and an alternate. If the actual one comes under attack or its ability to control the situation is disupted (e.g. a physical move) the alternate takes over. If both command posts are out of action a subordinate command post "steps up" to command the formation. In the case of an infantry battalion one of the company command posts would step up and take charge.
Command posts are often abbreviated to CP (pronounced "See Pee").
Moble command posts are often mounted on special armoured vehicles and include extra radios, map boards, etc. for the commander and his staff.
