Transportation

Ball bearings can be found in a wide variety of machines and gadgets. If you take a look at one of them you may notice how perfectly smooth they feel and appear. How do they get like that? Find out how ball bearings are created in this article.

You see gears in just about anything that has spinning parts - car engines, transmissions, electric toothbrushes... Learn what these gears are doing and get to the bottom of the "gear ratio" concept!

By Marshall Brain

You see backhoe-loaders on nearly every construction site around town. Learn how these amazing machines work and what they are able to do.

By Marshall Brain & Tom Harris

At first glance, it looks like a high-tech scooter. But people who have tried out the Segway claim that it is much, much more. Find out what's going on inside the Segway and what makes it so unique.

By Tom Harris

The only passenger plane that flies faster than the speed of sound, and can get from New York to London in less than four hours, is calling it quits. Learn how this amazing plane works.

By Craig Freudenrich, Ph.D.

It doesn't seem like twisted rope and wooden gears or levers would be able to produce the force and speed needed to launch heavy loads a great distance.

By Yara Simón

Although the amount of fuel may seem high, when you do the math, it's actually not so bad.

By Talon Homer

Contrails are those long white clouds that form in the wake of an airplane flying at altitude. What causes these contrails and what are they made of? Learn the answer to this question in this article from HowStuffWorks.

I would like to know how airplanes can fly upside down and do loops. How does the fuel get to the engine if the plane is upside down?

Thomas the Tank Engine is a merchandising phenomenon that includes small wooden train sets, video tapes, books, clothing, an official Web site and tons of fan sites. But wait, what exactly is a "tank engine" anyway?

How do the engines breathe in diesel submarines? Don't internal combustion engines need a lot of oxygen to run? Where would all of this oxygen come from when the sub is underwater?

Do commercial jets have locks on the doors and ignition keys? If not, what keeps someone from stealing them?

When flushing the toilet in a passenger airplane, I'm amazed by the huge noise it makes -- like a powerful vacuum cleaner. Can you explain what makes this noise?

When I was a kid, my Aunt had constantly flowing water from a natural spring down the hill. She said the water was pumped uphill using a hydraulic ram. This device ran constantly and didn't need any electricity! What is a hydraulic ram and how does i

How are people able to breathe inside a submarine? What do they do to keep the air breathable?

By HowStuffWorks.com Contributors

Steam engines powered all early locomotives, steam boats and factories -- they fueled the Industrial Revolution. Learn how the steam engine produces power!

By Marshall Brain & Yara Simón

Bearings are the invisible heroes inside many mechanical devices. Learn about all different kinds of bearings, including 5-foot ball bearings that keep buildings on solid footing.

By Karim Nice

Magnetic levitation trains, aka maglev trains, can travel much faster than even bullet trains, with less environmental impact. But they're very expensive to build. So, what's the future of maglev trains?

By Kevin Bonsor & Nathan Chandler

Right around the fall months you may have heard the phrase 'punkin chunkin.' Have you ever wondered what exactly that is, or how the machines that launch pumpkins work?

Tower cranes rise 150 feet in the air and lift up to 19 tons. Plus, they actually build themselves! They're simply amazing. Learn how these structures accomplish such feats.

By Marshall Brain

Ever wonder what's happening inside that huge jet engine as you're cruising along at 30,000 feet? Jets, helicopters and even some power plants use a class of engine called gas turbines, which produce their own pressurized gas to spin a turbine and create power.

By Marshall Brain

A car engine uses a four-stroke cycle -- how can two strokes accomplish the same tasks? Learn all about the two-stroke engine, where it's used and how it compares to a four-stroke.

By Marshall Brain

Were these things invented to make your hair stand on end? Find out how Van de Graaff generators create static electricity and why they were invented in the first place.

By John Zavisa

Not so long ago, the world's naval forces worked entirely above water. But all that changed with the addition of the submarine to the standard naval arsenal.

By Marshall Brain & Craig Freudenrich, Ph.D.

How does a speedometer in an airplane work?