Alexander Graham Bell's telephone was the first of its kind to receive a patent in the United States and gain widespread commercial success. Bell was interested in sound on a conceptual level and used an observation about sound echoing from one piano to another to develop the technology that made telephone calls possible.
Widely recognized as the inventor of the telephone, Alexander Graham Bell was the son of a deaf mother, and according to the Telegraph, his father invented the first international phonetic alphabet. Bell's conceptual interest in sound waves led him to the brilliant realization that the human voice could be transmitted across space. Along with his assistant Thomas Watson, Bell made the first successful phone call in 1876, saying, "Mr. Watson, come here, I want you." Bell was 29, and Watson was just 22.
According to AT&T, the story that Bell only just managed to get his patent in before a competitor is not entirely true. Bell's patent for the telephone was for a working machine, whereas the other patent in question, filed by Elisha Gray, was for a concept that had not yet come to fruition. However, Bell's patent wasn't the first of its kind for this kind of machine; a man named Antonio Meucci had patented a device called the teletrofono in 1871, but he couldn't afford to renew it.