The front wheel plays an important role in two wheeled vehicles moving without falling over.

Stars wheeled overhead and every day was as long as a life age of the Earth.

For most small wheeled robots, they use a method called differential steering where the left and right wheel turns the opposite direction.

The first thing we did was we took a little bicycle mirror and we Band Aided it here, onto a gurney, a hospital trolley, so that when you were wheeled around by a nurse or by a doctor, you could actually have a conversation with them.