Broadband communication is a term that refers to the high-speed transmission of data. This transmission may occur over a physical channel, such as a digital cable television system or digital subscriber line (DSL), which uses traditional copper telephone lines, or through the air, as in a satellite television system. The definition of broadband varies from country to country. In the United States, the Federal Communications Commission (FCC) requires a system to support a minimum transmission speed of 200 kilobits per second (kbps) to qualify as broadband. A kilobit is 1,000 bits. Bits are the primary units that represent all digital data. A system is generally considered broadband even if it supports 200 kbps or more in only one direction of transmission.