  radar is an object-detection system that uses radio waves to determine the range, altitude, direction, or speed of objects. it can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. the radar dish or antenna transmits pulses of radio waves or microwaves that bounce off any object in their path. the object returns a tiny part of the wave's energy to a dish or antenna that is usually located at the same site as the transmitter. radar was secretly developed by several nations before and during world war ii. the term radar was coined in 1940 by the united states navy as an acronym for radio detection and ranging.mcgraw-hill dictionary of scientific and technical terms / daniel n. lapedes, editor in chief. lapedes, daniel n. new york ; montreal : mcgraw-hill, 1976. [xv], 1634, a26 p. the term radar has since entered english and other languages as a common noun, losing all capitalization. the modern uses of radar are highly diverse, including air traffic control, radar astronomy, air-defense systems, antimissile systems; marine radars to locate landmarks and other ships; aircraft anticollision systems; ocean surveillance systems, outer space surveillance and rendezvous systems; meteorological precipitation monitoring; altimetry and flight control systems; guided missile target locating systems; and ground-penetrating radar for geological obs
Air_traffic_control Aircraft_instruments Avionics Measuring_instruments Microwave_technology Navigational_equipment Radar Science_and_technology_during_World_War_II Targeting_(warfare)