There are about 165 major rivers in the world. These major rivers are long and wide enough to be classified as major rivers with large volumes of water flowing through them every day. They have tributaries and provide fresh water to billions of people. There are thousands of smaller rivers, but the exact number of small and large rivers in the world is difficult to determine.
The major rivers of the world are the Amazon, the Nile and the Yangtze rivers. The Amazon is the largest river by volume of water and has a length of 6,516 kilometers. The Nile, at 6,695 kilometers long and the longest river in the world. The Mississippi-Missouri river system in the United States is more than 5,969 kilometer long.
Most rivers have their source in lakes, springs, wetlands and glaciers. They flow towards the sea where they empty their waters. However, there are a few inland rivers often called virgin rivers. They have their source and mouth inland. The Amu Darya and the Syr Darya are examples of inland rivers.
Rivers are the cradles of civilization. All the major civilizations such as the Mesopotamian, Indus Valley, the Egyptian and the Chinese civilizations have developed on the banks of rivers. Rivers are used as inland waterways for transportation and for producing hydroelectric power.