A permutation group is a group of permutations, or bijections (one-to-one, onto functions) between a finite set and itself.

yes form cayleys theorem . every group is isomorphic to groups of permutation and finite groups are not an exception.

{123, 132, 213, 231, 312, 321}

A permutation is an arrangement of objects in some specific order. Permutations are regarded as ordered elements.

A selection in which order is not important is called a combination. Combinations are regarded as sets.

For example, if there is a group of 3 different colored balls, then any group of 2 balls selected from it will be considered as a combination, whereas the different arrangements of every combination will be considered as a permutation.

i am a permutation is a awesome answer