Explain the differences to me?

[Ace Modder]

between....Cynicism, Pessimism and Skepticism ?

I've just been writing an email and was unsure which word is best to use, so can all three be explained?

 

[Ace Modder]

I think skeptical is when you actually know the facts, but expect a negative outcome which goes is against these facts.

But the other two, I'm struggling to work out the differences.