To maintain balance, it turns the wheels at just the right speed, so you move forward. Like your brain, the Segway knows when you are leaning forward. The Segway does pretty much the same thing, except it has wheels instead of legs, a motor instead of muscles, a collection of microprocessors instead of a brain and a set of sophisticated tilt sensors instead of an inner-ear balancing system. Instead of falling, you walk forward, one step at a time. If you keep leaning forward, your brain will keep putting your legs forward to kee­p you upright. Your brain knows you are out of balance, because fluid in your inner ear shifts, so it triggers you to put your leg forward and stop the fall. If you stand up and lean forward, so that you are out of balance, you probably won't fall on your face. To understand how this system works, it helps to consider Kamen's model for the device - the human body. This balancing act is the most amazing thing about the Segway, and it is the key to its operation. To turn left or right, the rider turns the right handlebar forward or backward. To move forward or backward on the Segway, the rider just leans slightly forward or backward.