Biography of Nikola Tesla, Discovered Alternating Current

He also developed the underlying technology for wireless communication

Nikola Tesla
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Nikola Tesla (July 10, 1856–January 7, 1943), who was a trained electrical and mechanical engineer, was one of the most influential inventors of the 20th century. Eventually holding over 700 patents, Tesla worked in a number of fields, including electricity, robotics, radar, and wireless transmission of energy. Tesla's discoveries laid the groundwork for many of the 20th century's technological advances.

Tesla’s life played out like a science fiction movie. He often had flashes of light in his mind that revealed the design of innovative machinery, which he committed to paper, constructed, tested, and perfected. But all was not easy. The race to light up the world was fraught with rancor and animosity.

Fast Facts: Nikola Tesla

  • Known For: Discovered alternating current (AC), influenced the modern electrical-supply system
  • Also Known As: Father of AC Current, Father of the Radio, The Man Who Invented the 20th Century
  • Born: July 10, 1856 in Smiljan, Croatia
  • Parents: Milutin Tesla, Đuka Tesla
  • Died: January 7, 1943 in New York City
  • Education: Realschule in Karlstadt, the University of Prague, the Polytechnic Institute in Graz, Austria (studied mechanical and electrical engineering, but dropped out)
  • Published Works: The Problem of Increasing Human Energy (published in The Century Magazine in 1900), Experiments With Alternate Currents of High Potential and High Frequency (1904, republished in 2012), My Inventions: The Autobiography of Nikola Tesla (1919)
  • Awards and Honors: AIEE Edison Medal (1917), University of Paris Medal (1937), The Medal of the University St. Clement of Ochrida, Sofia, Bulgaria (1939), IEEE Nikola Tesla Award (presented annually to an individual or team that has made an outstanding contribution to the generation or utilization of electric power)
  • Notable Quote: "If you want to find the secrets of the universe, think in terms of energy, frequency and vibration."

Early Years

Tesla was born on July 10, 1856, to Milutin Tesla, a Serbian Orthodox priest in Smiljan, Croatia, and Đuka Tesla. He credited his innovative quest to his mother, an inventive homemaker who created appliances such as a mechanical eggbeater to help with the home and farm. Tesla studied at the Realschule in Karlstadt, the University of Prague, and the Polytechnic Institute in Graz, Austria, where he studied mechanical and electrical engineering.

Work With Edison

In 1882, the 24-year-old Tesla was working for the Central Telephone Exchange in Budapest when the idea for a rotating magnetic field flashed through his mind. Tesla was determined to turn his idea into a reality but he was unable to find backing for the project in Budapest; thus, Tesla moved to New York in 1884 and introduced himself to Thomas Edison through a letter of recommendation.

Edison, the creator of the incandescent light bulb and the world’s first electric lighting system in the commercial blocks of lower Manhattan, hired Tesla at $14 per week plus a $50,000 bonus if Tesla could improve Edison’s electric lighting system. Edison's system, a coal-burning electric generating station, was limited to supplying electricity to about a one-mile radius at the time.

AC vs. DC

Although Tesla and Edison shared a mutual respect for one another, at least at first, Tesla challenged Edison’s claim that current could only flow in one direction (DC, direct current). Tesla claimed that energy was cyclic and could change direction (AC, alternating current), which would increase voltage levels across greater distances than Edison had pioneered.

Since Edison didn't like Tesla's idea of alternating current, which would impose a radical departure from his own system, Edison refused to award Tesla the bonus. Edison said the offer of a bonus had been a joke and that Tesla didn't understand American humor. Betrayed and insulted, Tesla quit working for Thomas Edison.

Scientific Rival

Seeing an opportunity, George Westinghouse (an American industrialist, inventor, corporate entrepreneur, and a rival of Thomas Edison in his own right) bought Tesla’s 40 U.S. patents for the polyphase alternating current system of generators, motors, and transformers.

In 1888, Tesla went to work for Westinghouse in order to develop the alternating current system. At this time, electricity was still new and feared by the public due to fires and electric shocks.

Edison fed that fear by using smear tactics against alternating current, even stooping to the electrocution of animals to scare the community into believing that alternating current was much more dangerous than direct current.

In 1893, Westinghouse outbid Edison in lighting up the Columbian Exposition in Chicago, which allowed Westinghouse and Tesla to show the public the marvels and advantages of electric light and appliances via alternating current.

This demonstration of alternating current convinced J.P. Morgan, an American investor who had originally financed Edison, to back Westinghouse and Tesla in their design for the first hydroelectric power plant in Niagara Falls.

Built in 1895, the new hydroelectric power plant transmitted an amazing twenty miles away. Large AC generating stations (using dams on large rivers and power lines) would eventually link across the nation and become the type of power supplied to homes today.

A Wireless World

Winning the "War of Currents," Tesla sought a way to make the world wireless. In 1898, Tesla demonstrated a remote-controlled boat at the Madison Square Garden Electrical Exhibition.

The following year, Tesla moved his work to Colorado Springs, Colorado, in order to construct a high-voltage/high-frequency tower for the U.S. government. The goal was to develop a wireless transmission of energy using the vibrating waves of the earth to generate unlimited power and communications. Through this work, he lit 200 lamps without wires from a distance of 25 miles and shot man-made lightning into the atmosphere using a Tesla coil, a transformer antenna he had patented in 1891.

In December 1900, Tesla returned to New York and began work on a “World-System” of wireless transmissions intended to link up the world’s signal stations (telephone, telegraph, etc.). However, the backing investor, J.P. Morgan, who had financed the Niagara Falls project, terminated the contract upon learning that it would be “free” wireless electricity for all to tap into.


On Jan. 7, 1943, Tesla died at the age of 86 of coronary thrombosis in his bed at the Hotel New Yorker where he resided. Tesla, who had never married, had spent his life creating, inventing, and discovering.

Upon his death, Tesla held over 700 patents, which included the modern electric motor, remote control, wireless transmission of energy, basic laser and radar technology, the first neon and fluorescent illumination, the first X-ray photographs, the wireless vacuum tube, the air-friction speedometer for automobiles, and the Tesla coil (widely used in radio, television sets, and other electronic equipment).


On June 21, 1943, the U.S. Supreme Court ruled in favor of Tesla as “the father of the radio” rather than Guglielmo Marconi who had received the Nobel Prize in Physics in 1909 for his contributions to the development of the radio.

The court’s decision was based on Tesla’s lectures of 1893 and possibly due to the fact that the Marconi Corporation had sued the U.S. government for royalties for using radio patents during World War I.

In addition to all that Tesla created, he also had many ideas that he didn't have time to finish. Some of these ideas included massive weapons. In a world still immersed in World War II and that was just beginning to split into East vs. West, ideas of massive weapons were coveted. After Tesla's death, the FBI seized Tesla's belongings and notebooks.

It is thought that the U.S. government used the information from Tesla's notes to work on building beam weapons after the war. The government set up a secret project, called "Project Nick," which tested the feasibility of "death rays," but the project was eventually shut down and the results of their experiments were never published.