Telecommunications is the process of communicating over a long distance. The most popular telecommunication methods today include telephone, radio, television, facsimile and computers. Most modern forms of telecommunications involve sending a signal of electrical, electromagnetic or optical energy from one location to another. In its earliest forms telecommunications consisted of smoke signals, ringing a bell or physically transporting a message between two places.

Electrical telecommunications began with the invention of the telegraph. The telegraph enabled detailed messages to be sent instantaneously between two locations. Advances in telecommunications are still occurring today, making it possible to send more information farther and faster than ever before. Electrical telecommunications evolved during the late eighteenth and early nineteenth centuries along with rapid advances in electricity and magnetism. As new discoveries were made in the fields of electricity and magnetism, they were incorporated into the telecommunication devices. Inventors in Europe and the United States worked on many communication devices during the same time period. People from many disciplines were interested in the field of telecommunications, including medical doctors, musical instrument makers and physicists.

Ever since the beginnings of time, people have been trying to communicate over distances greater than the human voice could reach. Early attempts included the use of smoke signals, signal fires, waving flags, and the moving arms of semaphores. Mirrors were also used to flash the image of the sun to distant observers.

After the discovery of electricity, wires were stretched from one point to another and an electric current was either allowed to flow through the wires or broken by a switch called a telegraph key. The electric current was first used to make marks on a paper tape, and later it was used to activate a "sounder" which made clicking sounds. The short and long times between the clicks could be decoded into letters from the alphabet.

This revolutionary discovery allowed people to communicate instantly over distances that had required days or weeks for horse or train-carried messages. Telegraph stations were set up along railroads first because the right-of-way had already been cleared and it was easy to set up poles to carry the telegraph wires. Railroad dispatchers sent messages via telegraph to control the movement of trains and the wires also began to carry messages telling of news events and business transactions. It has been said that the "electric telegraph" was the most significant invention of the nineteenth century.

The telegraph was an electrically operated device or system for distant communication (the first-ever invented) by means of visible or audible signals. The method used throughout most of the world was based in large part on the work of Samuel Morse in the mid-nineteenth century. It utilized an electric circuit set up by using a single overhead wire and employing the earth as the other conductor to complete the circuit. In the telegraph's simplest form, an electromagnet in the receiver is activated by alternately making and breaking the circuit. Reception by sound, with the morse code signals received as audible clicks, is the basis for a low-cost, reliable method of signalling. In addition to wires and cables, telegraph messages are now sent by such means as radio waves, microwaves and communications satellites. Telex is a telegraphy system that transmits and receives messages in printed form. Today the telegraph is less widely used, having been supplanted by telephones, facsimile machines, and electronic mail.