//Some will say prog-rock but a little pop mixed in - and imo prog-rock is more King Crimson and Pink Floyd than APP but still, can’t knock ‘em.
Can’t see a mention APP and Pink Floyd without pointing out that Alan Parsons was the sound engineer for Dark Side of the Moon.
The core of the APP came from the band "Pilot" of "It's Magic" fame, and Parsons also produced that song for them.