what is astigmatism?

Eyeball normally shaped like a ball so that the incoming rays or shadow can be captured at one point in the retina (sensitive area of the eye). In the astigmatism, the eye ball shaped like an oval or egg so that the light entering the eye shadow spreads a bit alias does not focus on the retina. This causes a shadow that looks to escape and was only seen clearly at one point only. In addition, a somewhat distant shadow will appear blurred and wavy.

I had an astigmatism when I was in sixth grade. I have to wear eyeglasses. The doctor told me that astigmatism can be inherited. It can be cured if detected early so he adviced me to wear glasses. When I was in high school my astigmatism was gone. Then right now in college I was detected to have astigmatism again.