1. Alexander Graham Bell invented the telephone in 1876, after years of experimenting with sound transmission.
2. Bell's invention of the telephone was a result of his work on improving telegraph technology.
3. Bell's breakthrough was in creating a device that could transmit the human voice over a wire, instead of just electrical signals.
4. Bell's first successful telephone transmission occurred on March 10, 1876, when he spoke into the device to his assistant, who heard the words clearly on the other end.
5. Bell's invention of the telephone revolutionized communication and laid the foundation for the modern telecommunications industry.