From its inception, one of the defining characteristics of the electro sound was the use of drum machines, particularly the Roland TR-808, as the rhythmic basis of the track. As the genre evolved, computers and sampling replaced drum machines in electronic music, and are now used by the majority of electro producers. It is important to note, that although the electro of the 1980s and contemporary electro (electronic dance music) both grew out of the dissolution of disco, they are now different genres.