Photo reconnaissance

Reconnaissance is a mission to obtain information by visual observation or other detection methods, about the activities and resources of an enemy or potential enemy, or about the meteorologic, hydrographic, or geographic characteristics of a particular area.

In military operations, reconnaissance is the exploration outside an area occupied by friendly forces to gain information about natural features and enemy presence.

Examples of reconnaissance include patrolling by troops (Long Range Reconnaissance Patrol, U.S. Army Rangers, cavalry scout, or military intelligence specialists), ships or submarines, manned/unmanned reconnaissance aircraft, satellites, or by setting up covert observation posts. Espionage normally is not reconnaissance, because reconnaissance is a military's special forces operating ahead of its main forces; spies are non-combatants operating behind enemy lines.

Often called "" (British and Canadian English) or "" (American and Australian English), the associated verb is reconnaître.

Traditionally, reconnaissance was a role that was adopted by the cavalry. Speed was key in these maneuvers, thus infantry was ill suited to the task. From horses to vehicles, for warriors throughout history, commanders procured their ability to have speed and mobility, to mount and dismount, during maneuver warfare. Military commanders favored specialized small units for speed and mobility, to gain valuable information about the terrain and enemy before sending the main (or majority) troops into the area, screening, covering force, pursuit and exploitation roles. Skirmishing is a traditional skill of reconnaissance, as well as harassment of the enemy.

Reconnaissance conducted by ground forces includes special reconnaissance, armored reconnaissance, amphibious reconnaissance and civil reconnaissance.

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Wikipedia