[6600gt]

I am now confused too. This is what I know:

The PIC's have an internal hardware PLL(Phase Loop Lock hardware multiplier). I can't find the setup of this of RC but if you connect a 10MHz crystal to a pic and turn on hardware PLL, its like running 40 MHz crystal.(Don't ask me how it does it, I have no clue, try the data sheet) But they might have just hooked it up directly to a 40MHz clock, I guess you can do it.

I see this everywhere Foso/4, I am guessing but I think it means frequency of the oscillator(clock). I might be screwing up the technical terms.

In the Data Sheet I found this "One instruction cycle consists of four oscillator periods...".

So 10 MIPS * 4 = 40MHz

oscillator is just a crystal or resonator that oscillates or resonates at a particular frequency.

Don't worry about it. All you need to know is that the processor executes at 10 MIPS