Dance music is a product of the late 20th century. In the late 1970s and early 1980s, the use of synthesizers and samplers became popular in the underground and popular music scenes of most western countries. Synthesizers are electronic instruments that mimic the sounds of traditional instruments but also enable the user to manipulate the features of sounds. Samplers are pieces of electronic equipment that are used to record short pieces of sound. These short recordings are then replayed as part of a piece of music, often being looped or played repeatedly. These electronic instruments were used extensively in the house and techno music of the 1980s and this is where dance music was born. The repetitive 4/4 beat of house and techno separates it from earlier popular music and is still a defining feature of dance club music.
House music was the forerunner of dance club music and is still extremely popular in contemporary dance clubs. The genre is characterized by a relentless 4/4 kick drum that drives every track. Piano, vocal and string parts are also typical of house tracks as is the extensive use of synthesized sounds. House music, like most modern dance music, tends to build up gradually throughout a track until climaxing with a crescendo or "drop," as it is termed within the dance scene. House music came out of the New York music scene.
Techno was developed in Detroit and evolved out of the house music coming from New York. Techno used the 4/4 kick of house music but added loud bass synthesizers and faster speeds. Detroit Techno was also influenced by European electronic music like that of Kraftwerk. Techno is hugely popular across Europe, the United States and much of the rest of the world.
Trance music is popular in modern clubbing. It is a fusion of techno and house music. Trance music has the repetitive 4/4 beat of its predecessors but instead of a creating a mechanical, technological atmosphere, trance uses more euphoric, melodious synth sounds and vocal lines.
Drum and Bass makes use of the Amen break, a drum break sampled from an old soul record called "Amen, Brother." This break is used in a lot of contemporary urban music, including hip-hop and jungle. In drum and bass, this break is repeated over and over again and fused with prominent bass and sub-bass lines. Drum and Bass DJ's are often accompanied by MC's (a vocal accompaniment or "rapper") in nightclubs.