A telephone network is a telecommunications network that connects

telephone A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into e ...

s, which allows

telephone call A telephone call is a connection over a telephone network between the called party and the calling party. First telephone call The first telephone call was made on March 10, 1876, by Alexander Graham Bell. Bell demonstrated his ability to "ta ...

s between two or more parties, as well as newer features such as

fax Fax (short for facsimile), sometimes called telecopying or telefax (the latter short for telefacsimile), is the telephonic transmission of scanned printed material (both text and images), normally to a telephone number connected to a printer o ...

and

internet The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a '' network of networks'' that consists of private, pub ...

. The idea was revolutionized in the 1920s, as more and more people purchased telephones and used them to communicate news, ideas, and personal information. During the 1990s, it was further revolutionized by the advent of computers and other sophisticated communication devices, and with the use of

dial-up internet Dial-up Internet access is a form of Internet access that uses the facilities of the public switched telephone network (PSTN) to establish a connection to an Internet service provider (ISP) by dialing a telephone number on a conventional telep ...

. There are a number of different types of telephone network: * A

landline A landline (land line, land-line, main line, home phone, fixed-line, and wireline) is a telephone connection that uses metal wires or optical fiber telephone line for transmission, as distinguished from a mobile cellular network, which uses ...

network where the telephones must be directly wired into a single

telephone exchange A telephone exchange, telephone switch, or central office is a telecommunications system used in the public switched telephone network (PSTN) or in large enterprises. It interconnects telephone subscriber lines or virtual circuits of digital syst ...

. This is known as the public switched telephone network or PSTN. * A

wireless network A wireless network is a computer network that uses wireless data connections between network nodes. Wireless networking is a method by which homes, telecommunications networks and business installations avoid the costly process of introducing ...

where the telephones are

mobile Mobile may refer to: Places * Mobile, Alabama, a U.S. port city * Mobile County, Alabama * Mobile, Arizona, a small town near Phoenix, U.S. * Mobile, Newfoundland and Labrador Arts, entertainment, and media Music Groups and labels * Mobile ( ...

and can move around anywhere within the coverage area. * A private network where a closed group of telephones are connected primarily to each other and use a gateway to reach the outside world. This is usually used inside

companies A company, abbreviated as co., is a legal entity representing an association of people, whether natural, legal or a mixture of both, with a specific objective. Company members share a common purpose and unite to achieve specific, declared go ...

and

call centre A call centre ( Commonwealth spelling) or call center (American spelling; see spelling differences) is a managed capability that can be centralised or remote that is used for receiving or transmitting a large volume of enquiries by telephone. ...

s and is called a private branch exchange (PBX). * Integrated Services Digital Network (ISDN) Public telephone operators (PTOs) own and build networks of the first two types and provide services to the public under license from the national government. Virtual Network Operators (VNOs) lease capacity wholesale from the PTOs and sell on

telephony Telephony ( ) is the field of technology involving the development, application, and deployment of telecommunication services for the purpose of electronic transmission of voice, fax, or data, between distant parties. The history of telephony is i ...

service to the public directly

References

Telecommunications infrastructure {{telecomm-stub

See also

References