Running board

A running board is a narrow step fitted under the side doors of a car or truck. It aids entry, especially into high vehicles, and is typical of vintage cars, which had much higher ground clearances than today's vehicles. It is also used as a fashion statement on vehicles that would not otherwise require it. The origin of the name running board is obscure; the first running boards predate automobiles and were installed on carriages as early as the 17th century. Whether the running board was named after the inventor or in reference to function is open to debate.

In the early 20th century, all automobiles were equipped with running boards. The necessity of using them was caused by the fact that first cars were designed with a narrow, high body bolted to the chassis. A running board served as a step to a vehicle's cabin and was wide enough to serve as a place to sit or even lie down for an adult.

During the 1920s and 1930s, car design was evolving rapidly to become more sleek and aerodynamic. It eliminated the need for running boards. The first automobile designed without running boards was the 1936 Cord. It changed the attitude towards running boards for many years ahead.

Running boards may also be used to stand on while the vehicle is moving. The name running board is also given to safety appliances for walking on top of rail cars.

The term also applied to the walkways on top of railroad boxcars. Originally, they were used by brakemen to travel from car to car to apply hand-operated brakes. With the adoption of the air brake this practice was abandoned. However the running board was still used as an observation point to pass hand signals to the train engineer when cars were being switched. The increased use of radio communication made this unnecessary. Today it is forbidden for anyone to be on top of a freight car while the train is in motion. The term is also used to describe the continuous step below all doors of classic trams on both sides as well as below the doors of old fashioned passenger cars.

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Wikipedia