# What is a permutation?

##### 1 Answer

A **permutation** is a sequenced selection of items from some collection.

#### Explanation:

For example if our collect were

One permutation would be

note that this is a different permutation than

(the order is significant).

Often a permutation may be specified as only a certain number of items selected from the given base collection.

For example, one possible permutation of

Sometimes we are interested in how many different permutations are possible.

Again using the collection of fruit as an example,

there are

So the number of permutations of