Jungle warfare is a term used to cover the special techniques needed for military units to survive and fight in jungle terrain. It has been the topic of extensive study by military strategists, and was an important part of the planning for both sides in many conflicts, including World War II and the Vietnam War. The jungle has a variety of effects on military operations. Dense vegetation can limit lines of sight and arcs of fire, but can also provide ample opportunity for camouflage and plenty of material with which to build fortifications.