Improvised Explosive Device

An improvised explosive device, or IED, is a bomb built and deployed outside conventional military manufacture and delivery, often incorporating military ordnance such as an artillery shell fitted with an improvised detonator, and commonly emplaced as a roadside or homemade bomb. The term was coined by the British Army during the Northern Ireland conflict to describe the booby-trap bombs built by the Provisional IRA, and it passed into wide American use during the Iraq War. IEDs are used mainly by guerrilla and insurgent forces and by state special-operations units conducting unconventional warfare, in preference to conventional standing armies. Devices of the same basic kind, sometimes called fougasses, were improvised for centuries before the term existed, and systematic large-scale use is recorded in German rearguard demolitions in the First World War and in the Belarusian Rail War partisan sabotage campaign against German rail lines in 1943 and 1944.