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I can't post a drawing at the moment but the difference is basically:
FSK is a constant signal which shifts in frequency. The frequency determines whether a 1 or 0 is being transmitted.
OOK is an interrupted signal which normally sits on one frequency but is turned on and off to carry data. Think of it as being like Morse code. If the signal is ON, it normally indicates a '1' and if it is OFF (nothing transmitted) it indicates a '0'.