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Ever wondered how that thing works? Explore the inner workings of many common devices and inventions, as well as those that aren't so common, such as compasses, gyroscopes and bug zappers.

How Crossbows Work

The crossbow, a weapon popular with Wookiees, vampire slayers and some modern hunters, looks like a cross between a bow and a rifle. Read about it’s fascinating history and uses.

How X-rays Work

X-ray machines seem to do the impossible: They see straight through clothing, flesh and even metal thanks to some very cool scientific principles at work. Find out how X-ray machines see straight to your bones. See more »

How strong are the magnets in an MRI machine?

How strong are the magnets in an MRI machine? Can they pull a watch of your arm or even more? Learn just how strong MRI magnets are on this page. See more »

I've heard that bug zappers can actually help transmit diseases -- how does that happen? Once the mosquito dies, how can a disease it was carrying be transmitted? See more »

I've heard of bank robbers being foiled by a "dye pack" put in their money stash. What is a "dye pack"?

Dye packs are often used to foil bank robbers. Learn about dye packs in this article. See more »

How does a Galileo thermometer work?

One of my co-workers has an interesting thermometer on his desk. It is a glass tube with different-colored floating things in it. What kind of thermometer is this, and how does it work? See more »

How does a rebreather work?

How does a rebreather work? See more »

A friend of mine showed me this card that the image changed depending on the angle that you view it at. How does that work? See more »

See "Back to the Future 2"? Drool much over those hoverboards? Find out how these devices will work and see one that already does! See more »

How Ultrasound Works

Ultrasound can help doctors look inside a patient's body to see everything from heart valves to a moving baby. Find out how ultrasound works, what type of ultrasound techniques are available and what each technique can be used for. See more »

How does "bulletproof" glass work?

In a lot of movies you see windows that are 'bulletproof.' Does bulletproof glass really exist, and if so, how does it work? See more »