Telecommunication
is the transmission of signs, signals, messages, writings, images and sounds or intelligence of any nature by wire, radio, optical or other electromagnetic systems. Telecommunication occurs when the exchange of information between communication participants includes the use of technology. It is transmitted either electrically over physical media, such as cables, or via electromagnetic radiation. Such transmission paths are often divided into communication channels which afford the advantages of multiplexing. The term is often used in its plural form, telecommunications, because it involves many different technologies.
Early means of communicating over a distance included visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs. Other examples of pre-modern long-distance communication included audio messages such as coded drumbeats, lung-blown horns, and loud whistles. 20th and 21st century technologies for long-distance
communication usually involve electrical and electromagnetic technologies, such as telegraph, telephone, and teleprinter, networks, radio, microwave transmission, fiber optics, and communications satellites.
According to the SOLAS (Safety of Life at Sea) convention, every member of the Global Maritime Organization should provide coastal equipment in order to offer radio communication services with ships. Considering the importance of this action and according to the paragraph 6 of the article 3 of the organization's by-law regarding the management of telecommunication networks in the coast and sea, in order to contact the ships and subordinate ports, the Ports and Maritime Organization considered it as a responsibility of the organization and has been trying to establish coastal maritime communication stations with the aim of improving the maritime safety and performing its sovereignty duties.