Landline

A landline is a telephone connected to a fixed wired network and used in a specific location, such as a home, office, or shop. It differs from the mobile telephone, which operates via airwaves. The line connects the household equipment to a switching exchange owned by the telephone company, where calls are routed to the desired recipient.

This system was the dominant method of voice communication for more than a century. A key characteristic is that the number is tied to a location, not to a person; thus a home number serves all members of the household. In recent decades, its use has declined in many places as people have switched to mobile phones and internet services.

How it works

The telephone converts sound into electrical signals, then transmits them via copper wire. Early systems also supplied the small amount of electrical current the telephone required, allowing it to function even during a power outage in the home. Switching exchanges were initially operated manually by staff who physically connected wires, but were later replaced by automated and digital systems.

Related services

The telephone line was also used to transmit data, first via modem and later with DSL technology, which provided high-speed internet over the same copper wire. In many locations, households obtained internet through the telephone line, although fiber is now increasingly replacing it. Additional services created from it include caller ID, voicemail, and call waiting.

Changes in usage

In many countries, the number of homes with telephone lines peaked in the late twentieth century and has since declined. In some regions, particularly in Africa and Asia, landlines never became widespread; people adopted mobile phones directly. However, landlines have remained robust in some areas because they are considered reliable for emergencies, and offices and factories continue to use internal systems.