vehicle traffic is the number of vehicles travelling on road.
Traffic lanes are lanes on the road that are divided into various speed limits, so you can choose your speed and stay on that lane.
A subway, train, plane, helicopters, and a bike
Mainly because people slow down to look. This is often referred to as rubbernecking.
Bicycles, tricycles, and unicycles with motors and yes it is possible i have a motor in my Bicycle.