Things are not always what they seem. Familiar objects can sometimes look distorted, bent, or out of alignment. It is often our eyes and senses which deceive us.
Spatial distortion plays a big role in our everyday lives. We live unconsciously by the law of perspective. We know how things should look in our three-dimensional universe. For an example, we know the railroad tracks on the left don’t really get smaller in the distance, they just look that way. It looks perfectly normal to our three-dimension world view.
If the railroad tracks were to get bigger in the distance we would suspect the scene as being unreal, or doubt our own senses. These illusions are designed to break the laws of common sense and perspective.