INTRODUCED IN THE 1930S AS A SYSTEM TO DETECT AIRCRAFT AND SURFACE

VESSELS FROM FAR AWAY OR IN POOR WEATHER CONDITIONS.

THE RADAR HELPED THE ALLIES WIN WORLD WAR 2.

TODAY ,IT IS ONE OF THE GREATEST CONTRIBUTORS TO AIR SAFETY.

BY BOUNCING RADIO WAVES OFF MOVING VESSELS,GROUND STATIONS CAN

DETECT THE POSITION OF OBJECTS IN THE SKY OR ON THE GROUND.

AN INGENIOUS SPIN-OFF WAS "STEALTH TECHNOLOGY," WHICH MAKES OBJECTS

OBJECTS IMPERVIOUS TO RADAR SIGNALS. MODERN FIGHTER JETS ARE COATED

WITH A MATEREAL THAT ABSORBS RADAR SIGNALS,MAKING THE PLANE

"INVISIBLE" TO RADAR SCREENS.