Reconnaissance is the military term for exploring beyond the area occupied by friendly forces to gain vital information about enemy forces or features of the environment for later analysis and/or dissemination.
Often referred to as recce (British & Commonwealth) or recon (US), the associated verb is reconnoitre in British English or reconnoiter in American English.
Examples of reconnaissance include patrolling by troops (rangers, scouts, or military intelligence specialists), ships or submarines, manned/unmanned aircraft, satellites, or by setting up covert observation posts. Espionage normally is not reconnaissance, because reconnaissance is a military force's operating ahead of its main forces; spies are non-combatants operating behind enemy lines.
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