Bicycle
Bicycle is a non-polluting vehicle. It is a vehicle which can be driven by the humans. They are introduced by the end of 18th century. But within short period of time more than one billion bicycles wee sold out all over the world. The fixed Non-moving bicycles are used in gym. It is also used in fitness centers. Fifty years ago the wheels of the bicycle is vary in its size. But now they are manufactured in same size. BSA is a popular company in manufacturing bicycles.