What is an example of a free form music composition?

Free form music, also known as aleatoric music, is a type of music composition in which the composer provides only general instructions or guidelines for the performers, leaving much of the musical content up to the performers' interpretation and improvisation. This can include elements such as the order, duration, or repetition of musical phrases or sections, or the use of aleatoric (chance-based) elements such as the throwing of dice or the drawing of cards.

One example of a free form music composition is the piece "Indeterminacy" by John Cage, composed in 1958. In "Indeterminacy," Cage provides performers with a set of musical "events" (written on separate cards) and instructions on how to combine and sequence them. The performers are free to choose the order, duration, and repetition of these events, as well as the instrumentation and spatial arrangement of the performance. This allows for a wide range of possible interpretations and realizations of the piece, each performance becoming a unique and unrepeatable experience.