why do cars drive on different sides of the road in different countries?

Answer 1

Here is the actual history
Originally everyone in Europe and Great Britain rode horses or drove their wagon on the left,so your right hand was free to hold the sword and defend yourself.However Napoleon was left handed and therefore preferred to ride on the right,with his left hand free.With Europe conquered,he forced everyone to ride his way.The British never were subdued by him and so still ride on the left.The US drives on the right because we were aided by the French during the Revolution.India drives on the same side as the Brits,the US and Europe drive on the right,and in Mexico they drive all over the road.

Answer 2

haha! thats a really good question, my guess is just to be different.

but im sure someone will make up something and give you a better explanation!! :]