Thomas Alva Edison is the most successful and well-known inventor of all time, with more than a thousand patents to his name. His best-known inventions are the incandescent lamp, the phonograph, and motion pictures, but he also contributed inventions for telegraph systems.

Others also invented some of the devices we associate with Edison, but he often made them better and he got people to use them. His success began with hard work; for example, he performed thousands of experiments to find a suitable filament that would resist the intense heat that results when producing light.

Another factor that made Edison a successful inventor was a keen interest in anything mechanical. As a teenager he worked as a telegraph operator and was repeatedly fired because of his constant tampering with the equipment.

Edison’s success is often attributed to his business sense, but this is open to question. His first major patent, a vote recorder for Congress, did not rouse interest –– one congressman told Edison that legislators wanted to keep voting records vague. Edison then vowed to make only inventions for which there was demand. Although correct about the electric light, his efforts with electric automobiles were superseded by the internal combustion engine. His list of possible applications for his phonograph included a dictating machine for letter writing, spoken books, teaching of speech, reproduction of music, archiving of voices of famous people, music boxes and toys, speaking clocks, study of language, educational recordings, and transmission of recorded messages over the telephone. Not only is recording of music halfway down the list, but initially Edison resisted even the idea. Possibly, his partial deafness was a factor in his failure to recognize the importance of recorded music; in any case, all of his other ideas have come to pass, although nearly always using magnetic tape (or, more recently, digital and laser) technology instead of his purely mechanical method.

There are other examples of Edison’s inability to foresee the uses to which his inventions might be put. He fought against projection for motion pictures, and believed that more money was to be made on peep shows than in movie houses. Consequently, although Edison showed that motion pictures were possible and made some of the early films, credit for the cinema outside of the United States is usually granted to the Lumière brothers of France, who projected motion pictures for small audiences from the first.

Where Edison’s business acumen was more evident was in the development of manufacturing and distribution related to his inventions. The electric generator had been available for decades when Edison opened the first power plants in London and New York City. He correctly recognized that his light bulbs would be of no use unless electric power was available and that money was to be made not only by selling the bulbs, but also by supplying the electricity.

Edison was not much interested in science for its own sake. In 1883 he discovered the basic principle of the vacuum tube (or valve), still known as the Edison effect, but he paid no attention to something for which he failed to see a use.