What is a river system?

A river system consists of a river and all of its tributaries. The main river is called the trunk or main stem. Tributaries are streams or rivers that flow into the main river. Tributaries can also have tributaries of their own, which are called sub-tributaries.

The size of a river system can vary greatly. Some river systems are very large and drain a large area of land, while others are quite small and only drain a small area. The Amazon River system is the largest river system in the world, and it drains an area of over 7 million square kilometers.

River systems are important because they provide water for drinking, irrigation, transportation, and industry. They also provide a habitat for many plants and animals.