Hydrology as a scientific field is concerned with the study of existence, properties, quality and distribution of water on Earth. It branches out into subdomains of surface water, ground water and marine hydrology. There has been rapid progress in this field and its applications are finding their way across multiple industries. Some of the most prominent applications are power generation, irrigation, providing potable water for consumption, etc. This book is a compilation of chapters that discuss the most vital concepts and emerging trends in the field of hydrology. Some of the diverse topics covered in this book address the varied branches that fall under this category. It is an essential guide for both academicians and those who wish to pursue this discipline further.