There are two ways of driving in the world: if the driver’s seat is on the left and cars travel on the right side of the road, it is called “left-hand driving”, as it is in China, while the other way of driving is called “right-hand driving”, as it is in Britain. Nowadays, around 65% of the world’s population drives on the right of the road, while the rest is used to driving on the left.
Though no one knows the exact reasons, it seems likely that people in ancient times travelled on the left. Roman coins show pictures of horsemen passing on each other’s right. And right-hand people generally got on a horse from the animal’s left. Obviously, it’s safer to do this at the left side of the road, and it makes sense for the horse to be ridden on the left.
A change happened in the late 1700s. When Napoleon conquered nations, he forced them to travel on the right side of the road, which spread left-hand driving throughout Europe. However, Britain still stuck with the right-hand driving rule and countries which were part of the British Empire (帝国) were made to follow. This is why India, Australia and the former British colonies (殖民地) in Africa continue to drive on the left. One exception is Egypt, as that country was defeated by Napoleon before becoming part of the British Empire.