Subsets chosen from a larger set of objects in which the order of the items in the subset does not matter. For example, determining how many different committees of four persons could be chosen from a set of nine persons. (See also, Permutations)

The total number of independent possible choices.

Used to determine whether the starting hand is playable, based on the number of outs possible from just the three cards.

Subsets chosen from a larger set of objects in which the order of the items doesn’t matter (for example, the number of different committees of three that can be chosen from a group of twelve members).

Subsets of a larger number of items (e.g., the number of different teams of three that can be chosen from a group of 21).