Question

What is the difference between permutations and combinations?

Answer 1

use permutations when ordering matters (like if you want to know how many possible arrangements you can make)
use combinations when ordering does not matter(like how many ways can I choose 3 things out of 9)

Answer 2

Permutations - position important (although choice may also be important)
Combinations - chosen important,
which may help you to remember which is which.

Answer 3

Thanks!