Rebetiko, plural rebetika, occasionally transliterated as rembetiko or rebetico, is a term used to designate previously disparate kinds of urban Greek music which in the 1930s went through a process of musical syncretism and developed into a more distinctive musical genre. Rebetiko can be described briefly as the urban popular song of the Greeks, especially the poorest, from the late 19th century to the 1950s, and served as the basis for further developments in popular Greek music. The music, which was partly forgotten, was rediscovered during the so-called rebetika revival, which started in the 1960s and developed further from the early 1970s.