Just to exemplify the coolness of creating four different versions of each level track:
Sonic CD - Wacky Workbench (Past)
Sonic CD - Wacky Workbench (Present)
Sonic CD - Wacky Workbench (Bad Future)
Sonic CD - Wacky Workbench (Good Future)
(On top of that, there are four additional, very different tracks for the same level for the NA version of the game.)
"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram