Chaff refers to large quantities of passive reflecting
material deployed in the atmosphere to counter or confuse enemy
radar. Chaff was (almost) simultaneously introduced during World
War II (1943) by the Germans and the British. The
British called their version of chaff window.
of functionality, chaff is capable of providing a
form of camouflage from the radar system. Chaff
can be deployed extensively and cooperatively by a number of
platforms to produce a cloud through which the radar cannot
penetrate. Some radar systems are confused by clouds of chaff whilst others sense the chaff clouds
as false targets.