A T1 line is a dedicated transmission connection between a service provider and client that uses 2 twisted pair copper wires to transmit and receive data or voice traffic. It is a type of copper or fiber optic telephone line that can carry more data than traditional telephone lines. A T1 line can transmit data at a speed of 1.544 Mbps, which is about 60 times faster than a traditional modem. It can carry 24 digitized voice channels, making it optimal for commercial buildings. A T1 line is typically carried over an HDSL encoded copper line. T1 lines have been the industry standard for decades thanks to their capacity, reliability, and functionality. They are still utilized today for high-speed data transmission, internet access, and voice, depending on the type of T1 and the configuration. A T1 line might cost between $1,000 and $1,500 per month depending on who provides it.