Optical illusions

Are these red lines are straight or wavy? These lines are straight although they do not appear so Is the shape below a perfect square? Black dot seems to appear everywhere in the intersection Circle Illusion, stare the circle in the centre of the picture. Scroll this page up and down and watch the center square magically move. Stare at the image below and slowly move your head toward and away from the screen. Look at the red lines, do they appear to be wavy? Focus on the middle of the square Spider Effect Sponsored Links: