Interest in performance-oriented sunglasses has surged in recent years, along with participation in outdoor activities such as mountain biking, snowboarding, rock climbing, kayaking, skiing, golfing and in-line skating. Durable and specialized performance sunglasses...

Sunglasses: Frequently Asked Questions.
What exactly are UV rays?
Ultraviolet (UV) rays are located just past the violet portion of the visible light spectrum; sunlight is the main source.
UV light is broken into three different types: UVA, UVB and UVC.

Polarized sunglasses have been popular for years with boaters and fishermen who need to reduce reflected glare from the water surrounding them. But now that many others who spend time outdoors have discovered the benefits of polarized lenses, interest in these types of sunglasses has soared.