Originally Posted by Wikipedia

Disco is a genre of dance music. Its popularity peaked during the middle to late 1970s. It had its roots in clubs that catered to African American primarily but later found it's acceptance among the gay, psychedelic and other communities in New York City and Philadelphia during the late 1960s and early 1970s. Disco was a reaction by New York City's mainstream as well as black, and Hispanic or Latino and heterosexuals against both the domination of rock music and the demonisation of dance music by the counterculture during this period. Women embraced disco as well, and the music eventually expanded to several other popular groups of the time.

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Musical influences include funk, Latin and soul music. The disco sound has soaring, often reverberated vocals over a steady "four-on-the-floor" beat, an eighth note (quaver) or sixteenth note (semi-quaver) hi-hat pattern with an open hi-hat on the off-beat, and a prominent, syncopated electric bass line sometimes consisting of octaves. The Fender Jazz Bass is often associated with disco bass lines, because the instrument itself has a very prominent 'voice' in the musical mix. In most disco tracks, strings, horns, electric pianos, and electric guitars create a lush background sound. Orchestral instruments such as the flute are often used for solo melodies, and unlike in rock, lead guitar is rarely used.