If you are shortsighted, close items will be sharply in focus, but you have trouble seeing in the distance. Myopia (nearsightedness or short-sighted) occurs when the cornea is too steep and rays of light are focused in front of the retina. Another way of explaining it is that the eye is too long and the curvature of the cornea is too steep so the image falling directly on the retina is out of focus.
How to Correct Short-Sightedness
Are you Short-Sighted?
It is common for short-sightedness to occur in adolescence or younger. You may notice it if you have difficulty reading signs or recognising people in the distance, particularly when there is poor lighting.