Although it no longer exists, the telegraph is an early predecessor to the Internet and the World Wide Web.

Telegraph was the first reliable service to transmit information almost instantaneously over large distances, even continents and oceans. It used copper wires that could carry electrical signals from one station to the next, allowing almost instantaneous communication across long distances for the first time in history.

The first telephone systems were based on the telegraph technology that was already in place. These telephones, which people now often refer to as landlines but which have the official name of public switched telephone networks (PSTNs), use wires to carry signals from one phone to another. The telephone device itself converted sound to electrical signals and then converted the signals back to sound at the other end.