Improvised explosive device
An Improvised explosive device is a weapon typically used by terrorists and guerillas. It typically consists of an explosive of varying size fastened to a trip wire. When a vehicle or person moves the trip wire, the explosive will go off. Often abbreviated to just IED, these weapons have caused a large percentage of American troop deaths in Iraq. As of late 2003, anywhere from 40%-60% of all attacks by insurgents in Iraq were began with detonation of an IED.