March 7th, 1876
The Telephone is patented by Alexander Graham Bell

Alexander Graham Bell is granted a patent for a device he calls the telephone.

Although there is some controversy over the credit for the invention as several similar devices were demonstrated between 1849 and 1876, the fact that Bell's patent was registered first (albeit only by a matter of hours) meant that the credit (both intellectual and financial) is largely attributed to him.

On 10 March 1876, three days after the patent was granted, Bell first transmitted speech- the now famous line, "Mr. Watson, come here, I want you."