Telecommunication
The conventional telephone was invented independently by Alexander Bell and Elisha Gray in 1876. Antonio Meucci invented the first device that allowed the electrical transmission of voice over a line in 1849. However Meucci's device was of little practical value because it relied upon the electrophonic effect and thus required users to place the receiver in their mouth to "hear" what was being said. The first commercial telephone services were set-up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London.
Telephone tapping
The history of voice communication technology begins in 1876 with the invention of Alexander Graham Bell’s telephone. In the 1890s, “law enforcement agencies begin tapping wires on early telephone networks”. Remote voice communications “were carried almost exclusively by circuit-switched systems,” where telephone switches would connect wires to form a continuous circuit and disconnect the wires when the call ended). All other telephone services, such as call forwarding and message taking, were handled by human operators. However, the first computerized telephone switch was developed by Bell Labs in 1965. This got rid of standard wiretapping techniques.