Okay, the factorial (the exclamation mark) means you multiply the number by each whole number down to 1. For example, 4! = 4 times 3 times 2 times 1
The C stands for combination, which means how many groups of a certain amount could you pick from the whole group. For example, if you have 3 books in a bag, and you grab 2, there are three combinations of 2 that you could grab. (1 and 2, 1 and 3, and 2 and 3, if you name them with numbers)
The P stands for permutation, which is just like a combination except that the order matters. So grabbing book 1 and then book 2 out of the bag would count as different than grabbing 2 and then 1.
Both of these have formulas, which you can find in your textbook or on wikipedia or whatever (I'll edit them in in a minute.)
edit: this seems like a pretty good site -
http://www.andrews.edu/~calkins/math...xts/prod02.htm