GLASSES WITH SINGLE VISION LENSES
Single vision lenses offer one correction, and most often are made for general, everyday use, including driving. Single vision lenses are also used to make reading glasses for those who need spectacles to see near object clearly, or have a second, other than their general use eyeglass, for reading. Single vision sunglasses however are usually made for general use but you can order one as reading glasses, too.
GLASSES WITH MULTIFOCAL LENSES
Multifocal lenses (also called varifocal, PAL or progressive addition lenses) provide an all-in-one solution to correct so called “presbyopia”, when your eyes, from about the age 40 onwards, start needing “additional help” to focus on objects close up, like reading a book or looking at your phone screen. Multifocal lenses combine far (distance), intermediate (like computer screen) and near (reading) corrections which merge continuously into one another, providing sharp image at all distances.
Your prescription will likely contain an addition (ADD) value if you need multifocal lenses.