what is a 2 sided drawing called or is there a website i can view them?

Question

ex: a drawing of a picture of an old woman but when u flip it over its a younger woman, or a picture of a witch but flip it again and its a princess who know what those are called or a website i can view them?

Answer 1

Optical illusions are very common and these are what you are referring.

http://www.google.com/search?hl=en&q=optical+illusions

Have fun and don't get too dizzy.

Answer 2

optical illusions....I have these cool pictures, fascinating,


http://www.optillusions.com/dp/1-11.htm