As used in this article, the following terms shall have the meanings indicated:
The person operating or in control of a vehicle.
The standing of a vehicle, whether occupied or not, other than temporarily, for the purpose of, and while actually engaged in, receiving or discharging passengers or loading or unloading merchandise or in obedience to traffic regulations or traffic signs or signals.
Any device in, upon, or by which any person or property is or may be transported upon a public highway.