"Guest worker" music is the music for and by (labour) migrants and their families in West Germany around the 1960s until 1980s. These often socially critical songs describe living and working in Germany as well as the separation from family and friends and other topics relevant to the migrants. They were characterised by the use of different languages and music styles. Some musicians were extremely popular, for example Cem Karaca or Yüksel Özkasap. Özkasap was known as “nightingale of Cologne” and won several gold records in the 1960s and 1970s.