I'm not entirely sure about this, but if I remember it correctly, then Genesis was 8 bit, and mega drive was 16 bits.
Either way, I hope you all remember those days where mega cd and 32x were supposed to dominate the world with their 92 bit combination.

Actually, there was only one of those games that got released. It played pretty damn good, even though I never bought it.

"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram