Nikola Tesla is indeed considered one of the most important and prolific inventor of the twentieth century. Most of his work was related to electricity, and he is rightly considered the father of the alternating current (AC) motor, besides many other relevant discoveries in the fields of electromagnetism, radio, and radar (such as, for instance, the fluorescent light, the arc lightning, and the wireless remote control). Everybody agrees on the fact that Nikola Tesla did not receive during his life the awards and the consideration he deserved for his work and his valuable contribution to the world of science. He died in 1943, when he was on his own with very few friends, in the room 3327 of the Hotel New Yorker, where he had lived for the last ten years of his life.

Nikola was born between the 9^th and the 10^th of July 1856 in the small village of Smiljan, in Croatia (at that time part of the Austro-Hungarian Empire). He was the fourth of five children and soon demonstrated during his childhood a strong interest towards mechanical and electrical systems. In 1875 he was able to enter the Polytechnic of Gratz (today in the Czech Republic), but after one year he had to leave it because the bursary was not renewed due to his nationality. However, in Gratz he had a chance to see and learn the basic principles of DC motors, and later he decided to work initially in Budapest and later in Paris for an Edison Company as an electrical engineer. It was at that time that Nikola started to think about the AC induction motor: initially he just conceived it in his mind (he had the great gift of a fervent imagination), and then he was even able to design and build a working prototype with his own resources. However, nobody seemed to be interested to this promising application in Europe, so in 1884 he decided to sail to the USA with only four cents in his pockets.

Arrived in New York, Nikola initially worked for Thomas Edison, with the task of improving the generators for producing direct current (DC). During that period, Tesla and Edison begun their battle for the currents: Tesla was a strong supporter of the AC current (anticipating its advantages in the transmission and distribution of electricity), whereas Edison strongly defended the DC current, in order to protect his investments in direct current equipment and facilities. Edison’s lighting systems, supplied by direct current, were inefficient and weak. Moreover, the main disadvantage of that system was that it could not be transported more than two miles since it was not possible to obtain the very high voltage required to cover great distances; for this reason, every two miles it was necessary to deploy a DC power station. On the contrary, alternating current (with a typical frequency of 50-60 Hz) can be more easily stepped-up to higher voltage level, reducing power losses and dispersions, and is therefore more suitable to cover great distances: today we know that history gave reason to Nikola.