Myopia, also known as short sightedness is the condition in which distant objects appear blurry. A short-sighted person will usually have good vision at close range, but will experience difficulties focusing on objects of details that are further away.
With myopia, light entering the eye focuses in front of the retina. This occurs because either the eye has grown too long, or the focusing components of the eye are too strong
A diagram of a normal eye v a shortsighted eye.
As you can see, in the diagram of the normal eye, light enters the eye, and focusses perfectly onto the back of the eye (the retina).
With a shortsighted eye, the light focusses in front of the retina, and causes the image that forms on the retina to be blurred. Thus, causing distance vision to be blurred.
Anyone can develop myopia at any age; however the great majority of cases of people developing myopia occur between the ages of 10 to 30.
At the moment there is no cure for short-sightedness however the best and safest way to manage your condition is to wear glasses. It is becoming ever more popular to wear contact lasers or more recently undergo laser treatment.