Telecommunications, also referred to as telecom, is that the exchange of data over significant distances by electronic means and refers to all or any sorts of voice, data and video transmission. this is often a broad term that has a good range of data transmitting technologies like telephones (wired and wireless), microwave communications, fiber optics, satellites, radio and tv broadcasting, the web and telegraphs. An entire, single telecommunications circuit consists of two stations, each equipped with a transmitter and a receiver. The transmitter and receiver at any station could also be combined into one device called a transceiver. The medium of signal transmission are often via electrical wire or cable (also referred to as "copper"), glass fiber , electromagnetic fields or light. The free space transmission and reception of knowledge by means of electromagnetic fields is named wireless communications. the only sort of telecommunications takes place between two stations, but it's common for multiple transmitting and receiving stations to exchange data among themselves. Such an appointment is named a telecommunications network. the web is that the largest example of a telecommunications network. Data is transmitted during a telecommunications circuit by means of an electrical signal called the carrier or the carrier. So as for a carrier to convey information, some sort of modulation is required. The modes of modulation are often broadly categorized as either analog or digital.