Anton Karl Karas (7 July 1906 – 10 January 1985) was an Austrian zither player and composer, best known for his internationally famous 1948 soundtrack to Carol Reed's The Third Man. His association with the film came about as a result of a chance meeting with its director. The success of the film and the enduring popularity of its theme song changed Karas' life.

Source: Wikipedia (https://en.wikipedia.org/wiki/Anton_Karas)