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Chemists discover how blue light speeds blindness

Blue light from digital devices and the sun transforms vital molecules in the eye's retina into cell killers, according to optical chemistry research at The University of Toledo.

GPS tracking down to the centimeter

Researchers at the University of California, Riverside have developed a new, more computationally efficient way to process data from the Global Positioning System (GPS), to enhance location accuracy from the meter-level down ...

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Telephone

The telephone (from the Greek: τῆλε, tēle, "far" and φωνή, phōnē, "voice") is a telecommunications device that transmits and receives sound, most commonly the human voice. It is one of the most common household appliances in the developed world, and has long been considered indispensable to business, industry and government. The word "telephone" has been adapted to many languages and is widely recognized around the world.

The device operates principally by converting sound waves into electrical signals, and electrical signals into sound waves. Such signals when conveyed through telephone networks — and often converted to electronic and/or optical signals — enable nearly every telephone user to communicate with nearly every other worldwide. Graphic symbols used to designate telephone service or phone-related information in print, signage, and other media include ℡, ☎, ☏, and ✆.

This text uses material from Wikipedia, licensed under CC BY-SA