Developed in 1962 by Bell Laboratories, the original purpose of the T1 Connection was to greatly increase the number of simultaneous telephone calls that a telephone network could handle. This system is used in the United States, South Korea and Kyoto, Japan while in Europe there is a similar but not directly compatible system called E-Carrier. With modern digital communications the T1 Line as it’s commonly called, is capable of data transmissions of up to 1.544 Mbits of data per second.
T1 Connections are usually fiber optic but some are still copper. Many large office phone systems require a T1 connection and big businesses often get a T1 connection for their networks as well. It is possible to move roughly 60 times as much data over a T1 line than over a typical domestic modem. A T3 line is of even larger capacity and can handle 23 T1 lines, this is usually called a backbone connection. There are other even faster types of internet backbone connections all the way up to 9.6 gigabit per second capacity.