5.1 surround sound

5.1 surround sound ("five point one") is the common name for six channel surround sound audio systems. 5.1 is the most commonly used layout in home cinema. It uses five full bandwidth channels and one low-frequency effects channel (the "point one"). Dolby Digital, Dolby Pro Logic II, DTS, and SDDS are all common 5.1 systems. 5.1 is also the standard surround sound audio component of digital broadcast and music.