Hemispheres divide the earth in half. They divide it both horizontally and vertically. The equator divides the northern hemisphere from the southern hemisphere. The Prime Meridian line divides the earth into the eastern and western hemisphere. When living in the northern hemisphere, the temperature gets colder the further north you travel. When living in the southern hemisphere, the temperature gets colder the further south you travel.
This is because you are moving further away from the equator. Both lines are invisible and are at zero degrees latitude and longitude. Sometimes you may hear about the western countries or westernization, people who say that are referring to the western hemisphere which is made up of North America, South America and Central America.
