The process of using computation (whether performed by a computer, other electronics, mechanical devices, or manually) to synthesize melodies, harmonies, and rhythms, as opposed to synthesizing timbres. Algorithmic composition goes back to the Middle Ages, but began getting serious attention with the modernism movement in classical music in the 20th century. At first, this consisted mainly of using gambling devices as random number generators to select notes, but researchers quickly moved on to trying to find algorithms that would mathematically encapsulate melodies that humans generally find to be pleasing or interesting.
A branch of artificial intelligence focuses on algorithmic composition, and how the human mind perceives music. A number of research efforts have focused on using computers and electronics to generate compositions. Little of this has had any exposure outside of academia. The Triadex Muse of the early 1970s was an electronic device that composed melodies depending on how the user set a group of switches on its panel. In the late 1970s, as the microprocessor revolution was getting started, John Simonton wrote a piece of software called Pink Tunes, which Larry Fast used to produce the Synergy album Computer Experiments Vol. 1.