I am a protector. I sit on a bridge. One person can see right through me, while others wonder what I hide. What am I?

The answer to the riddle is sunglasses. These everyday items serve as a protector (Review) for our eyes, shielding them from the sun's harsh glare and harmful ultraviolet (UV) rays. They sit comfortably on the bridge of the nose, a familiar perch for anyone who wears them. While the wearer sees clearly through the tinted lenses, the dark exterior often obscures their eyes from others, leading to a sense of mystery about what thoughts or expressions might be hidden behind them. This dual function of protection and concealment perfectly matches the riddle's description.

The concept of eye protection from intense light is ancient. Indigenous Inuit people, for instance, crafted snow goggles from bone, ivory, or wood with narrow slits to prevent snow blindness caused by the sun's reflection off ice and snow. In 12th-century China, judges reportedly used flat panes of smoky quartz to obscure their facial expressions in court, preventing witnesses from seeing their emotions during trials. Later, in the 18th century, English optician James Ayscough experimented with tinted lenses, believing blue or green hues could correct vision impairments, and Venetian gondoliers wore green-tinted glasses to reduce glare from the canals.

Modern sunglasses gained widespread popularity in the 20th century. Sam Foster began mass-producing inexpensive celluloid sunglasses in 1929, finding a ready market on the beaches of Atlantic City. Hollywood movie stars further cemented their status in the 1920s and 30s, initially using them to protect their eyes from bright studio lights, which quickly evolved into a powerful fashion statement. Today, beyond their stylish appeal, sunglasses are crucial for eye health, offering essential protection against UV radiation that can lead to serious conditions like cataracts and macular degeneration, making them far more than just an accessory.