Engineering

All steel is not the same, and Damascus steel has a reputation for being the best. But is today's Damascus steel the same as that forged centuries ago?

By Carrie Whitney, Ph.D.

Why does air cool down when pushed around by an electric fan? You would think that air molecules in motion would be creating friction, and therefore increasing the ambient temperature instead of decreasing it. So why do you feel cooler?

If you've ever seen a construction site, you may have noticed that the general plans for construction are drawn out in the form of blueprints. What exactly are blueprints, though, and how are they made? Find out in this article.

Rome is famous for having large public fountains that work without the use of any kind of mechanized pump. How were these fountains able to generate enough water pressure without a motor? Check out this article for the answer to this question.

I am curious about the ignition system in my lawn mower. I know that a spark plug creates a high-voltage spark, and I know in my car the electricity for the spark comes from the battery. My lawn mower doesn't have a battery, so where does the electricty come from?

Is there an easy way to measure the height of a cell phone tower in my neighborhood?

As an invention, Cold Heat seems to have everything. But reviewers -- both professionals and average users -- either love the tool or hate it, and some people question whether it's really "new" at all.

By Tracy V. Wilson

A female Android designed to look like a 20-something Korean woman is capable of making facial expressions and holding a simple conversation.

By Cameron Lawrence

A tunnel can be simply defined as a tube hollowed through soil or stone, but actually constructing a tunnel is a challenge. Find out how tunnels are built.

By William Harris

When pyramids come to mind, most of us think of Egypt, but pyramids exist in many parts of the world. How were they constructed without earth-moving or heavy-lift machinery? And most of all, why were these amazing structures built?

By Craig Freudenrich, Ph.D.

We are a species of bridge builders. Since time began, humans have engineered structures to vault over obstacles with the help of logs, stone, steel and, of course, ingenuity. So, what keeps our bridges steadfast and strong?

By Robert Lamb, Michael Morrissey & Patrick J. Kiger

Whether they're sorting out scrap metal or helping us unlock the secrets of the universe, electromagnets are pretty nifty devices. What's so great about magnetism on demand? We'll electrify you with the details.

By Marshall Brain, Chris Pollette & Yara Simón

Did you know that airplanes and space shuttles use the utterly low-tech gyroscope for navigation? Discover the secret behind gyroscopic motion!

By Marshall Brain & Desiree Bowie

The refining of iron ore is one of our most historically significant achievements. The element is so important that primitive societies are measured by the point at which they learn how to refine it.

By Marshall Brain & Robert Lamb

Whether they make you think of Hurricane Katrina or Led Zeppelin, levees are a critical safety feature for low-lying areas located near water. Why do they break?

By Marshall Brain & Robert Lamb

Rail guns leave gunpowder-based weapons in the dust (one can hit a target 250 miles away in six minutes). So why isn't the military using them? Find out how rail guns can be used and learn about the limitations of this technology.

By William Harris

With the help of Q, James Bond can breeze through a security system that requires the villain's irises, voice and handprint. Biometrics isn't just for the movies. Real-life businesses and governments are using it. Check it out.

By Tracy V. Wilson

It walks, it talks and it works as a receptionist. Honda engineers have been busy creating the ASIMO robot for more than 20 years, and it shows.

By Lee Ann Obringer & Jonathan Strickland

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.

By Tom Harris

A robot and a human being are made up of the same basic components. And with each passing decade, robots become more lifelike. Find out how robots operate and the marvelous things they're already doing.

By Tom Harris & Chris Pollette

CAT scans take X-ray imaging to a whole new level. Find out how a CAT scan machine uses "slices" to form a 3-D computer model of a patient's insides.

By Tom Harris

The twin towers of the World Trade Center were true originals -- their history is one of innovation, persistence and grand ideas.

By Tom Harris & Yara Simón

Plastics can be shaped or molded into any form, and they're everywhere -- in your car, computer, toys and even bubble gum. But because they don't degrade, they cause big problems when it's time to throw them out.

By Craig Freudenrich, Ph.D.

Robot armies could soon account for up to one third of all vehicles currently in service. Learn about robot armies and robot army development.

By Jonathan Strickland

The Hoover Dam holds back 10 trillion gallons of water. That's enough to cover the entire state of Connecticut. How much damage would be done if the dam broke?

By Patty Rasmussen