Right- and left-hand traffic facts
The driving side of a road is the side on which traffic flows. Each country says whether traffic will keep on the right-hand or left-hand side of the road. This is sometimes called the rule of the road. This basic rule makes traffic move easier. It also reduces the risk of head-on collisions. Today about 66.1% of the world's people live in countries who drive on the right-hand. 33.9% live in countries that drive on the left-hand.
Right- and left-hand traffic Facts for Kids. Kiddle Encyclopedia.