“For almost as long as we’ve had digital computers, enterprising programmers have been trying to teach them how to play music. Perhaps the most challenging remaining hurdle is the spontaneous back-and-forth flow of improvisation. Machines are quick to learn when it comes to rolling out standard chord progressions and following predictable rhythms. But they turn out to be lousy at riffing, precisely because riffing is a much more chaotic sort of pattern, one that relies on intuition more than structure. But as daunting as it sounds, free improv may yet become a part of the computer’s musical repertoire, thanks to sophisticated software programs.”