Glasses – also called eyeglasses (formal), spectacles, or specs (informal) – are frames bearing lenses worn in front of the eyes, normally for vision correction or eye protection. Safety glasses are a kind of eye protection against flying debris or against visible and near visible light or radiation. Sunglasses allow better vision in bright daylight, and may protect against damage from high levels of ultraviolet light. Other types of glasses may be used for viewing visual information (such as stereoscopy) or simply just for aesthetic or fashion values.

Historical types of glasses include the pince-nez, monocle, lorgnette, and scissors or scissors-glasses.

Modern glasses are typically supported by pads on the bridge of the nose and by temple arms placed over the ears. CR-39 lenses are the most common plastic lenses due to their low weight, high scratch resistance, low dispersion, and low transparency to ultraviolet and infrared radiation. Polycarbonate and Trivex lenses are the lightest and most shatter-resistant, making them the best for impact protection.

An unpopular aspect of glasses is their inconvenience. Even through the creation of light frames such as those made of titanium, very flexible frames, and new lens materials and optical coatings, glasses can still cause problems during vigorous sports.

Mercury and the Woodman

A Woodman was felling a tree on the bank of a river, when his axe fell into the water. Mercury (14) … and asked him the reason he was sad. After diving into the river several times, Mercury finally returned the woodman’s missing axe. The Woodman was overjoyed at recovering his (15) … . Mercury was so (16) … with his honesty that he rewarded him with the other two axes.