Techno is a form of electronic music that emerged in Detroit, Michigan, in the United States during the mid-to-late 1980s. The first recorded use of the word techno in reference to a specific genre of music was in 1988. Many styles of techno now exist, but Detroit techno is seen as the foundation upon which a number of sub-genres have been built. Many producers use retro electronic musical devices to create what they consider to be an authentic techno sound. Drum machines from the 1980s such as Roland's TR-808 and TR-909 are highly prized, and software emulations of such retro technology are popular among techno producers.