9 Eyeglasses
(Read more about how we developed the rankings.)
Call them glasses, cheap oakley holbrook polarized specs, grannies, frames or peepers your local four eyes cheap oakley sunglasses can't live without them. Eyeglasses and other vision correction tools have had a staggering effect on the daily lives of millions. Without them, about a third of the world's population would spend their days wandering around in a haze.
Corrective lenses make workers more productive and accurate, and allow people to work into old age. Eyewear encourages the spread of literacy. And they've helped promote the idea that humans can overcome their own physical imperfections.
Early human civilizations were at the whim of their failing eyes the ancient Romans would have slaves read to them when they grew too old to see oakley frogskins cheap properly. Italian craftsmen learned how to oakley frogskins precisely mill these reading stones, and by 1286, they were making lenses that could be held in a frame in front of a person's eyes.
Later versions perched directly on the nose. For nearly 500 years, people struggled to keep the things on their face. Not long after, in 1730, a London optician, Edward Scarlett, added rigid sidepieces that rested atop the ears. In the 1780s, Benjamin Franklin invented the bifocal.
The more modern history of the eyeglass has oakley holbrook more to do with getting rid of this faithful tool; we've invented ever thinner and lighter lenses made of plastic instead of glass. In the 20th century we lost the frames all together, as contact lenses became an increasingly popular option. And today, laser surgery is helping many people see perfectly without corrective lenses at all.
Slide Show: The 20 Most Important Tools
Other important vision tools include bifocals, the monocle, contact lenses, sunglasses and safety glasses.
Corporate Connections: Vision getting fuzzy? You can get an eye exam and a new pair of glasses at retail outlets such as LensCrafters or Pearle Vision both owned by Italian eyewear giant