[Haskell-cafe] Types

Hello, I´ve a small question about Haskell. It´s really vague explained in "Haskell in 10 minutes" and sometimes it's really detailed explained which is very hard for people who just got into Haskell to read. Can someone explain me something about the type Integral? What exactly is it? I know that 2 is something of the type Integral, however what does this differ from Int? The same question goes for Fractional and Floating, what exactly is their commonality and what exactly is their difference? Thank you for explaining these basic things to me.