Even though most individuals have one eye that is stronger than the other, over-the-counter reading glasses have the same prescription in both lenses. Eye glasses purchased from your eye doctor, on the other hand, may be adjusted to meet the prescription your eyes require. These prescriptions are usually written for a person who needs glasses for distance vision only. Generally, glasses we buy in stores are identical in strength and quality for each lens; however, they can be altered by changing the thickness or style of the frame. A frame that's too thin or too thick will cause problems for someone who needs corrective lenses for their eyes. Corrective lenses serve two purposes: to improve distant vision and near vision. They're often called "prescription lenses" because the ophthalmologist who fits them needs to know your current prescription (i.e., how far back the optic nerve extends from the back of the eyeball) as well as your desired prescription (i.e., what degree correction you need for near and far sight). Many people think that they can't wear corrective lenses because they don't want to be seen wearing glasses, but this is not true. Glasses are an accessory worn on the head that can be just as fashionable as any other piece of jewelry. Some popular styles of glasses include rectangular, round, square, and half-rim.