At age 28, Nikola Tesla arrived in New York with four cents in his pocket and a letter of introduction to Thomas Edison, and proceeded to revolutionize the modern world. Born on July 9, 1856, in Smiljan (present-day Croatia), Tesla devoted his life to electrical science. His development of alternating current (AC) electrical systems gave civilization a practical way to transmit power across vast distances, directly enabling the power grids that light and heat every home today. He also invented the induction motor, the Tesla coil, and pioneered early radio technology. Though he died nearly penniless in 1943, his ideas outlasted his obscurity: the SI unit of magnetic flux density bears his name, and his vision of wireless energy transmission continues to inspire researchers in renewable energy and wireless charging alike.