successes over the number of trials without any replacement. Let us say we have a bag full of red and green balls and we have to find the probability of picking a green ball in 5 attempts but each time we pick a ball, we do not return it back to the bag. This is an apt example of the hypergeometric distribution.
For larger N, it is very difficult to calculate the hypergeometric distribution but when N is small, it tends to the binomial distribution in this case.