The American inventor Thomas Edison successfully filed and obtained 1,093 United States patents. His first patent application was executed while he was 21 years old on October 13, 1868. Edison's U.S. patents can be grouped into the general categories of electric power and light, phonographs and sound recording, telegraphy and telephony, batteries, mining and ore milling, miscellany, cement and motion pictures.
Edison's career as an inventor began in Newark, New Jersey, with his successful development of improved telegraph devices. It was his 1877 invention of the phonograph, however, that brought him to attention. The public reaction to displays of Edison's invention was unprecedented. The Washington Post described a display of the new device presented by Edison to Congress and the U.S. President in 1878 as a scene "that will live in history." Edison soon became a celebrity and gained the nickname "The Wizard of Menlo Park" after the section of Middlesex County, New Jersey where he had set-up his laboratory. The area has since been renamed Edison Township in honor of the famous inventor.
Edison is also known for his invention of the first commercially practical light bulb and his development of one of the first systems for the distribution of electric power. He established the first electric public utility company in New York City and began supplying DC power to 59 lower Manhattan customers in 1882. By 1887, Edison had 121 power stations in operation, but his DC systems were eventually replaced by the AC power distribution method championed by his adversary George Westinghouse. Edison also attempted to develop a practical X-ray device, or fluoroscope, but dropped the project after his assistant was severely injured by radiation exposure.