One of Ayler's key free jazz recordings is "Spiritual Unity", including his often recorded and most famous composition, "Ghosts", in which a simple spiritual-like melody is gradually shifted and distorted through Ayler's unique improvisatory interpretation. Ultimately, Ayler serves as an important example of many ways which free jazz could be interpreted, as he often strays into more tonal areas and melodies while exploring the timbral and textural possibilities within his melodies. In this way, his free jazz is built upon both a progressive attitude towards melody and timbre as well as a desire to examine and recontextualize the music of the past.