You can also read about them in stories, or look them up on the Internet. Maybe you have been lucky enough to travel abroad to other countries on holiday.

Today's tourists want to experience distant places for themselves. The Arctic and Antarctic are popular because of their beautiful landscapes. But tourism isn't always a good thing. Visitors bring money but they also bring problems. Boats and planes are big polluters. It may become necessary to restrict the numbers of visitors in certain parts of the polar regions.

Some countries are very rich and some are very poor. The poor ones are known as 'developing' countries. These places are often in debt and owe a lot of money to other countries. The richer, or 'economically developed countries' have most of the resources. We should try to find ways of sharing the world's resources.