Which lake contains 70 small floating islands? What is the name given to the study of lakes? Which lake is at risk of turning into a desert within 20 years? The world has many types of lake, some were created by melting glaciers, others form high up in the craters of extinct volcanoes. Find out about the incredible size of these lakes, the animals and plants that make their homes here, and the people who live on islands within some of them.