Literally, "little war", a strategy of fighting by a weaker side against a more powerful one using irregular, (civilian) warriors in occupied territory. Methods include deception, sabotage, assassination and propaganda, rather than open fighting, Success depends on gaining support from the people of the area promising them liberation from oppression. See TERRORISM.
Military and paramilitary operations conducted in enemy held or hostile territory by irregular, predominantly indigenous forces. See also unconventional warfare. (JCS Pub 1-O2) hasty attack: In land operations, an attack in which preparation time is traded for speed in order to exploit an opportunity. (JCS Pub 1-02)
Fighting in which small independent bands of soldiers harass an enemy through surprise raids, attacks on communications and the like.
(DOD, NATO) Military and paramilitary operations conducted in enemy-held or hostile territory by irregular, predominantly indigenous forces.
The term was invented in to describe the tactics Spain used to resist Napoleon, though the tactic itself has been around much, much longer. Literally, it means "little war." Guerilla warfare features cells and utilizes no front line. The oldest form of asymmetric warfare, guerilla warfare is based on sabotage and ambush with the objective of destabilizing the government through lengthy and low-intensity confrontation.
Guerrilla warfare (also spelled guerilla) is a method of unconventional combat by which small groups of combatants attempt to use mobile and surprise tactics (ambushes, raids, etc) to defeat a foe, often a larger, less mobile, army. Typically the smaller guerrilla army will either use its defensive status to draw its opponent into terrain which is better suited to the former or take advantage of its greater mobility by conducting surprise attacks at vulnerable targets, often deep in enemy territory.