When you are done, try the Lakes Quiz
Lakes are bodies of water surrounded by land. Lakes generally have fresh water, while oceans and seas have salt water. While lakes are a small percentage of the earth's total water, they are important for our economy and transportation.
A lake does not flow along a certain path as a river does. Lakes are larger than ponds.
Lakes were formed many thousands of years ago by glaciers. At that time, huge glaciers covered the earth. When the glaciers melted, some of the water that was over hollows in the earth became lakes.
Other ways lakes were formed include man made lakes, natural dams and craters formed in great volcanic explosions.
Lakes get bigger and smaller, depending on many factors. Lakes get smaller if they get filled up with silt or other material. They also dry up if they are not replenished with water through rainfall. Other lakes get deeper and bigger as rivers, rainfall and underground water make the lake expand.