This book delves into the increasing role of computers, particularly personal computers, in solving hydraulic problems across various engineering disciplines, with a specific focus on civil engineering’s hydraulics and water resources aspects. By leveraging Microsoft Excel, readers can easily grasp hydraulic principles and apply them to numerous problems without the need for complex software codes. The content has been refined through years of teaching Computational Hydraulics at the master’s level and based on the theses of numerous doctoral and graduate students. It is designed for undergraduate and graduate students who have completed prerequisite courses in fluid mechanics, hydraulics, and differential equations. The book can be studied over two semesters and is also valuable for engineers seeking insights into this subject. Throughout the book, theoretical concepts are reinforced with a wealth of examples solved at the end of each chapter. These examples comprehensively address practical complexities, enhancing the reader’s understanding. Moreover, the book covers not only “computer hydraulics” but also touches on “computational fluid dynamics” to provide a broader perspective on the subject, incorporating examples from environmental and structural engineering. The book introduces the finite differences method, a valuable tool for solving common partial differential equations used in fluid mechanics and hydraulics. It also presents alternative solution methods for three types of partial differential equations: elliptic, parabolic, and hyperbolic, supplemented with real-world applications and thorough solutions. In summary, the book is a comprehensive resource for those in the fields of civil and environmental engineering, offering practical problem-solving skills for real-world applications and serving as a guide for software developers creating programs related to finite difference numerical methods.