Ultraviolet Protection: Absorptive lenses intercept many of the sun's potentially harmful ultraviolet (UV) rays. If your eyes aren't protected, you eventually could develop clouding of the eye's natural lens (cataracts) or damage to the back, interior eye structure where images are processed (retina).

Glass or Plastic Eyeglass Lenses: You may hear different options, but the best UV protection for your eyes is found in highly absorptive modern plastic lenses such as polycarbonate or Trivex. Plus, plastic lenses are more lightweight than glass and easier on the nose. Most eyeglasses sold today have plastic lenses.

High Index Lenses: If you need significant correction for distance vision (nearsightedness), you'll want to opt for high index eyeglass lenses. These tightly compacted high index lenses are significantly thinner than regular lenses, and definitely more attractive than the "Mr. Magoo" thick glasses of the bad old days. Ask your optician if high index lenses will significantly reduce any lens thickness that may be associated with your particular prescription. If the answer is "yes," then pay the extra price for this option.

Tinted Lenses: Types and colors of eyeglass tints can vary in how well they absorb UV rays. Some people also use light tints for cosmetic effects to reduce the appearance of lines around eyes, as an example. Gray tints generally are recommended over green for sunglasses because they don't alter color perception, and also provide better absorption of UV rays. Yellow and brown tints sometimes are marketed as a way to create higher contrast vision, but this claim is disputed.

Anti-Reflective Coating: Early anti-reflective eyeglass lens coatings had a rough start, because they tended to erode away and attract greasy "goo" to lens surfaces. But newer generation anti-reflective coatings can be very effective. You don't have to choose anti-reflective coating, but you might consider it you want to reduce glare from computers or water surfaces. Anti-reflective coatings also are recommended to improve appearance of eyeglasses by reducing reflections or unattractive light "circles" that might otherwise show up within lenses.

Color Coating: Uniformly distributed color lens coatings have a predictable appearance, unlike tints that can vary depending on lens thickness. Color coatings also can be ordered with darker shading at the top of the lens fading into lighter shading at the bottom.

Mirror Coating: Many people buy mirror coatings for sunglasses because they're stylish. But mirror coatings also reduce extreme glare associated with water and snow.

Polarizing Lenses: If you work or play extensively in environments where glare is pervasive, such as around water and snow, these lenses are highly effective at reducing light from reflective surfaces. And you'll have an additional option of adding a lens coating that reduces glare still more.

Photochromic Lenses: Through a process that involves chemical reactions, photochromic eyeglass lenses automatically change from darker shading in bright lighting to neutral shading indoors.