[Mitch58]

Just getting into motors...

I noticed that Pendle have separate categories for S-Can and Short Can motors.

I can see that S-Cans perhaps all have a separate plastic end bell, whereas Short Can motors seem to be enclosed within a metal case. But I cannot believe there are separate categories just based on the design of the case.

Are there fundamental differences between these two motor types?

They are completely different motors and are not interchangeable without adaptors. The most common types of modern motors are FC-130 (S-can),FK-130 (Short Can) and FK 180 (long can). They all come in many RPM and different torque ratings for your individual wants/needs. If you go back a few years there are many other types, most of which are no longer produced