Nikola Tesla's inventions in electrical engineering focused primarily on the development of alternating current (AC) systems. His innovation revolutionized the generation and transmission of electricity, enabling efficient power distribution over long distances. Tesla's work on the Tesla coil, which demonstrated wireless transmission of energy, laid the groundwork for radio technology. Additionally, his explorations into magnetic fields, motors, and wireless communications have had a lasting impact on modern technology. Tesla's visionary ideas and relentless pursuit of innovation have made him a pivotal figure in the advancement of electrical engineering and the foundation for much of today’s electrical systems.