Reading glasses may be the only treatment you need if you have no other vision problems. As long as you have had an eye exam and you know the strength of the reading glasses you need, you can purchase them at a drugstore without a prescription. Your eye doctor can prescribe bifocals, trifocals, or progressive lenses if you are also nearsighted or farsighted, or if you don't want to have to take off your reading glasses to see far away.
Bifocals correct near and far vision ("bi" means two). A small half-circle in the lower part of the lens magnifies objects that are close. In some cases, the whole lower half of the lens magnifies these objects.
Trifocals correct near, middle, and far vision ("tri" means three). The lower part of the lens has two magnifying powers. One magnifies near objects. The other magnifies objects that are about an arm's length away.
Progressive lenses change magnifying power from near, to middle, to far vision. They do this slowly using a smooth transition. You don't notice a change from one power to the next. And you don't see any lines on the lenses. But the sides of the lenses will be blurry. That's because each lens promotes three fields of vision.