Electronic music is created through the use of computers and synthesizer. The 20th Century saw the emergence of a plethora of recording devices and computer technology. In the later decades, these innovations and gadgets helped foster the development of electronic music into a full-fledged music genre. Today, that genre is an umbrella term for several sub-genres.
Electronica dance is exactly what it sounds like it would be: electronic music made for dancing. It is divided into a variety of sub-genres including eurodance, techno, house, trance, and drum and bass. Each of these styles have distinct characteristics: Eurodance has a pop aesthetic and is often looked upon as the cheesiest of the electronica dance genres. Techno sounds robotic. House has a disco flair. Trance is often described as being the most free-form of the genres and is based on short, sampled sounds. Drum and bass moves at a speedy tempo.
Techno music the sub-genre of electronica dance that sounds the most robotic. It was born in Detroit in the 1980s. Derrick May is credited with being its innovator. He, along with Juan Atkins and Kevin Sauderson, made electronic music to play in dance clubs. There are two instruments responsible for giving techno its signature percussive sound: the Roland TR-808 and the Roland TB-303. The Roland TR-808 is a drum machine that executes precise rhythms. The latter is a bass line sequencer that produces repetitive riffs. Techno classics include Cybotron's "Alleys of Your Mind" and New Order's "Blue Monday."
Electronica is not made for dancing. It is made for relaxing and includes the sub-genres down-tempo, ambient and chillout. All three genres can be likened to synthesized elevator music. Unlike electronica dance, electronica does not place a heavy emphasis on percussion or rhythm. The harmonies and the melodies define its sound. The music is sometimes criticized as being bland and New Age-like. Deep Forest, Sasha, and Tim Story are examples of electronica artists.