"Radar is a system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects" (Wikipedia). Thus Radar allows people to see things that otherwise would not be able to be seen. Radar has been key in expanding people's range of sight. For example radar on submarines has been a monumental discovery. Originally sailors had the ocean and knew nothing about what was around them. With the advent of radar everything changed, people now knew what was out there. Dismissing or confirming a number of beliefs.