Heinrich Rudolf Hertz would be 155 years old today, February 22, 2012. Hertz is known for his discovery of the existence of electromagnetic waves. Applications of his work are myriad, but the scientist himself didn't recognize them.
From a modern perspective, it's difficult to fathom how the first person to demonstrate the existence of electromagnetic waves didn't understand the implications of his discovery.
In the late 1880s, Heinrich Rudolf Hertz was teaching at Karlsruhe Polytechnic in Berlin when he first produced electromagnetic waves and measured their wavelengths and velocity. He wrote of the experiment, "In a perfectly dark room [the sparks] are visible to an eye which has been well rested in the dark," according to a 1957 Scientific American article.
His students wanted to understand the applications of his discovery, but Hertz told them, "It's of no use whatsoever." He felt that his experiment was merely an exercise to demonstrate the accuracy of previous calculations of the Scottish physicist James Clerk Maxwell.
Though Hertz himself didn't view his work as important, it didn't take long for others to realize its significance. "Three years ago, electromagnetic waves were nowhere. Shortly afterward, they were everywhere," said Sir Oliver Heaviside, an English mathematical physicist, in 1891.
Hertz's discovery sparked (pardon the pun) a race to turn this new understanding of electromagnetic waves into a device for communication.