Nikola Tesla (1856–1943) was a brilliant inventor, electrical engineer, and physicist best known for his contributions to the development of alternating current (AC) electrical systems, which became the standard power system used worldwide. Born in modern-day Croatia, Tesla moved to the U.S., where he worked with Thomas Edison before branching out on his own. He developed groundbreaking technologies such as the Tesla coil, wireless communication, and early radio. Despite his revolutionary ideas, Tesla struggled financially, and much of his work was under appreciated during his lifetime.