How many numbers of possible live card hands (hands in five-card poker) drawn without replacement from a standard deck of 52 playing cards?

Please give full details!

I will assume you are looking at one hand only.

Quite simple, you are simply looking at a selection any 5 of the 52 cards

C(52,5) = 2,598,960 or
52!/(5!47!) = 52*51*50*49*48/5!

Next question: suppose 4 players are playing, how many possible hands are there ?

(most calculators have a nCr function)