"Guerilla" refers to a form of irregular warfare in which small groups of combatants use tactics like ambushes, sabotage, and hit-and-run attacks to fight larger traditional military forces. This strategy relies on mobility, surprise, and the support of the local population, making it effective in asymmetrical conflicts. The term is derived from the Spanish word "guerilla," meaning "little war," and became widely recognized during the Peninsular War in the early 19th century. Notable examples of guerilla warfare include the tactics used by Che Guevara in Cuba and the Vietnamese resistance against U.S. forces during the Vietnam War.