Book excerpt: Inland water primarily includes rivers, lakes, reservoirs, and wetlands. It also includes ponds, streams, groundwater, reservoirs, springs, cave waters, and floodplains. Most inland water bodies are lakes. Inland waters are unique ecosystems offering services and habitat resources. Food, fiber, medicine, climate management, flood and natural disaster mitigation, nutrient recycling, and drinking water purification are among the services they offer for human progress and poverty reduction. These ecosystems are also necessary for the generation of energy, transportation, leisure, tourism, and providing a home for flora and fauna. This book includes updates and recent research on all aspects of inland waters and the related field ( ecology, limnology, and environment protection). In this book, different chapters are presented with different sections that include water pollution and treatment, the hydromorphological quality of inland water, and the ecology and limnology of inland water. So, in this book, readers and scientists from different scientific fields will obtain updated information on all aspects of inland waters.