Telecommunications refers to technologies that allow communication over a distance, such as a telephone, radio, or internet. The basic elements of telecommunications systems include a transmitter that converts information into a signal, a transmission medium that carries the signal, and a receiver that converts the signal back into usable information. The internet provides many services globally like email, the world wide web, file sharing, and video calls. Satellites orbiting Earth can also facilitate telecommunications by transmitting signals for services like television, radio, internet, and phone calls from space. A satellite communication system consists of a satellite as the transmitter/receiver in orbit, and ground stations that send and receive signals to and from the satellite.