Hand organ is a term that refers to a type of musical instrument that is played by turning a crank with one hand while the other hand operates the keys or buttons. Some common synonyms for hand organ include barrel organ, hurdy-gurdy, crank organ, and street organ. A barrel organ is similar to a hand organ, but the music is produced by rotating a barrel with pins rather than turning a crank. A hurdy-gurdy is a stringed instrument that is played by turning a crank. A crank organ is similar to a hand organ, but it is typically smaller and more portable. A street organ is a type of hand organ that is often played by street musicians or organ grinders.