Red and green traffic lights have been around since the 1800s, when British traffic officers used to rotate gas lamps that burned red and green to control the movement of mostly horse-drawn vehicles.

There are a lot of hand signals which are used to communicate among motorcyclist while on the road, but some may not be as ...

Since the advent of motorized vehicles, manufacturers have put a lot of thought into making sure drivers can communicate crucial information to one another. Whether you're driving a car, truck, or ...

Doubles players can use a variety of hand signals to communicate with their playing partner during matches. Before a serve, the net player on the serving side can indicate to the server how they ...