The telephone is a communication device to be provided to transmit the human voice and be able to communicate at a distance.
To function, the telephone requires a terrestrial or spatial infrastructure: the telephone network. After having connected his fixed terminal or having switched on his mobile device, the user who has taken out a subscription with a telecommunications operator can make a telephone call to a recipient who is also connected by dialing his assigned number, which generally triggers the ringing tone. of the destination device. If the called party accepts the call, a telephone conversation can begin.
With the exception of emergency calls made to special numbers, calls made via a telephone have a cost, which is determined by call rates established according to their duration, the location of the recipient and the quality of the number. . Telephony thus represents an important market in the telecommunications sector.
