The invention of the radio was an important step towards modern telecommunications, following the invention of the telegraph and the telephone. Unlike the telegraph and the telephone, radio waves do not need any wiring for communication.
Although the existence of radio waves was predicted by James Maxwell in his equations, it wasn't until the 1890s that this technology was proven feasible to be used on a large scale. In 1899, Guglielmo Marconi transmitted the first wireless signal across the English Channel. By 1902, he made the first transatlantic transmission from England to Newfoundland.
Although much of our telecommunication systems are still grounded using fiber optics, we have found many important uses for radio waves. For example, it is due to radio waves that we now have cellphones, WiFi, GPS, satellites, space exploration, and of course, the radio.