Sunglasses are special eyeglasses with dark or tinted lenses that protect your eyes from bright sunlight. Unlike regular glasses that help you see more clearly, sunglasses block harsh light and harmful ultraviolet rays from the sun, making it more comfortable to be outside on sunny days.

The lenses in sunglasses are usually made from treated glass or plastic in shades of gray, brown, or green. Some sunglasses have polarized lenses that reduce glare from water, snow, or car windshields, which is especially helpful when you're at the beach or riding in a car. Athletes and pilots often wear specialized sunglasses designed for their activities.

People have protected their eyes from bright light for thousands of years. Inuit people carved flat pieces of ivory or bone with narrow slits to reduce snow glare. Ancient Chinese judges wore smoky quartz lenses, not for sun protection but to hide their facial expressions in court. Modern sunglasses as we know them were developed in the early 1900s, and they became popular in the 1920s when movie stars started wearing them to shield their eyes from bright studio lights and camera flashes.

Today, sunglasses serve both practical and fashion purposes. Some people collect different styles, while others stick with one trusty pair all summer long.