Mirror Symmetry

Bilateral symmetry is the symmetry everybody is aware of, and to many people this is symmetry itself. Bilateral symmetry occurs when two halves of a whole are each other's mirror images. Accordingly, bilateral symmetry is also called mirror symmetry.

		The left half of the butterfly and its mirror image depict the whole butterfly.
The right half of the butterfly and its mirror image also depict the whole butterfly; therefore the butterfly has mirror symmetry
If the two halves are not mirror images of one another, the application of a mirror does not recreate the original object or figure.
For example, the letter R does not have mirror symmetry.		The letter A, however, does have mirror symmetry.
		Tyger! Tyger! burning bright In the forests of the night, What immortal hand or eye Could frame thy fearful symmetry? – William Blake The Tyger