The term free jazz may have existed before Ornette Coleman's The Shape of Jazz to Come arrived in 1959.
Conventional jazz is chord-based with soloists improvising over each chord.
Coleman, in contrast, imagined harmony, melody, and rhythm as equal constituents.
He had to break through the walls that harmony builts to free the melody.
Melody was everything to him, even drummers played like melodic instrumentalists.
Coleman believed that in the beginning, drums were like the telephone, they carried the message. Coleman's music is more like a "party line."
The theory that held his music together was eventually called Harmolodics. A word that sums up his ideas about the equality of rhythm, harmony, and melody.
Coleman described his ideas in a 1983 manifesto titled Prime Time for Harmolodics.
Then, around 1995, the name harmolodic was changed to Sound Grammar.
In Harmolodic/Sound Grammar improvisation, musicians contribute equally on their own terms.
Each contribution is equally essential to the whole. No one player has the lead, anyone can come out at any time.
To Ornette, Music is a language of sounds that transforms all human languages.