The term camouflage only came into widespread use during the First World War, and the specialist camouflage units developed by the combatants at the time put the bulk of their efforts into the concealment of artillery, vehicles, observation posts and bunkers. It was not until the Second World War that all major combatant nations issued camouflage uniforms better designed to disguise profile, and also tailored to the appropriate theatre of war. Halftones, color; Illustrations, unspecified