Everyday Tech

How do batteries work? How much energy is your plugged-in gadget using? How do UPC codes work? Find this out and more with Everyday Tech.

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What do the UL marks on so many products mean?

A large number of electronic devices carry "UL" marks. You can find them on everything from Christmas lights to digital camcorders. What does this logo mean?

What is the difference between two- and three-pronged plugs?

Ever wonder why some appliance plugs have three prongs and others have only two? What does that third prong do? And what would happen if you plugged a three-pronger into a two-prong outlet with an adapter?

How Batteries Work

Batteries power all sorts of things -- they're in our cars, our PCs, our cameras, our cell phones. How do these tiny cans of chemicals provide power for so many of our daily conveniences?