New Delhi: The Google logo takes the form of electromagnetic waves (in Google colours - blue, red, yellow and green) to pay tribute to German physicist Heinrich Rudolf Hertz on his 155th birth anniversary. Hertz was born at Hamburg on February 22, 1857. &

Hertz was the first to broadcast and receive radio waves. His pioneering work laid the way for the development of radio, television and radar.&

The unit of frequency of a radio wave - one cycle per second - is named the hertz, in honour of Heinrich Hertz. &

Unlike recent Google doodles that used complex JavaScript and HTML5 for animated doodles, the Hertz Google doodle is a relatively simpler animated GIF image.

Hertz proved the existence of radio waves in the late 1880s. He used two rods to serve as a receiver and a spark gap as the receiving antennae. Where the waves were picked up, a spark would jump. Hertz showed in his experiments that these signals possessed all of the properties of electromagnetic waves.&

With this oscillator, Hertz solved two problems. First, timing English scientis James Clerk Maxwell's waves. He had demonstrated, in the concrete, what Maxwell had only theorised - that the velocity of radio waves was equal to the velocity of light. (This proved that radio waves were a form of light).&

Second, Hertz found out how to make the electric and magnetic fields detach themselves from wires and go free as Maxwell's waves. &

Hertz died at the young age of 36 on New Year's Day 1894. There is a lunar crater on the dark side of the Moon named after him.&

Unlike recent Google doodles that used complex JavaScript for animated doodles, the Hertz Google doodle is a relatively simpler animated GIF image.&

Google has, till the Hertz doodle, posted 1308 doodles on its home page since the first ever Google doodle back on August 30, 1998.&