Yoga

I've been receiving so many phone calls (which I refer to as 'prank calls') asking me to join this fitness club and that yoga class. First of all, I don't know where they got my number from. But I have to admit, they're good. (And they're usually Filipinos.) My question is, how different is yoga from, say, pilates? I'm sure it's like comparing apples and oranges, but let's just say - for argument's sake - that I'm stupid...