UV stands for ultraviolet, a band of spectrum invisible to the eye. Ultraviolet light consists of UVA, UVB, and UVC rays. UVC rays are stopped in Earth's atmosphere before they reach the eye, but UVA and UVB can both reach the eye and potentially damage it.

Choose glasses that claim to block at least 99 percent of UV rays -- UVA as well as UVB. Look for label reading "UV 400," since this designation means that the glasses block UV rays as small as 400 nanometers, providing 100 percent eye protection. Of course you need to protect your eyes from the glare caused by the visible spectrum as well. To accomplish this, select products that block 75 to 90 percent of visible light.

Polarized lenses are specially designed to filter out certain types of glare that tend to radiate upward from horizontal surfaces when sunlight bounces off of these surfaces. They are recommended for tasks such as boating, fishing, skiing, golfing, jogging, and driving. Most polarized lenses will bear a label identifying them as such.

An anti-reflective coating, applied to the backside of the lens, prevents any exposure from UV radiation behind you from reflecting off the lens into your eyes. When the lens in front of the eye is tinted the eyes dilate to accommodate to receiving less light, allowing even more UV into the eye from behind and reflecting off the lens. The anti-reflective coating also allows you to see more clearly because distracting reflections are cancelled out.

We are able to provide you with a wide range of sunglass options. If you normally wear glasses to correct your eyesight, you may be happy with a non-prescription pair of clip-ons or wraparound glasses that simply fit over your lenses. If you'd rather not wear that much equipment on your head all at once, you can order a pair of prescription "shades," or you can order glasses that darken when exposed to bright light.