River systems are networks of flowing water that include rivers, streams, and tributaries. They play a crucial role in shaping landscapes, providing habitats for wildlife, and supporting human activities such as agriculture and transportation. Rivers often originate from mountains or hills, flowing downhill due to gravity, and eventually empty into larger bodies of water like lakes or oceans. The components of a river system include the main river channel, its tributaries, and the surrounding floodplain. Watersheds are areas of land that drain into a specific river, collecting rainwater and melting snow. Healthy river systems are vital for maintaining ecosystems and providing fresh water for communities.