Visual Illusions

When the perception of an object does not line up with the reality of the object, an optical illusion will take place. 

The boat appears to be floating in mid air, but we are able to perceive that there must be water underneath.

There are two different images in one. There is a  tree with a woman walking through the forrest and there is a mans face.

Which way is the man looking? Initially you may see half of his face looking at you, but  upon taking a closer look, his nose and eye brows seem to be facing the side.