The study of movement, distribution and management of water on Earth and other planets is known as hydrology. It involves the use of various scientific techniques and analytical methods to solve problems related to water such as environmental preservation, water management and natural disasters. The primary areas of study in this field are water cycle, water resources and environmental watershed sustainability. This domain branches out into various fields such as hydrogeology, hydroinformatics, surface hydrology, drainage basin, chemical hydrology and isotope hydrology. The field has applications in a variety of areas such as calculation of rainfall, flood warning and forecasting, designing dams and bridges and estimating potential water resources. This book provides significant information of this discipline to help develop a good understanding of hydrology and related fields. It also attempts to understand the multiple branches that fall under the domain of hydrology and how such concepts have practical implications. For someone with an interest and eye for detail, this book covers the most significant topics in this field.