The application of mathematical methods in different fields such as engineering, science, industry, business and computer science is known as applied mathematics. It combines mathematical science with specialized knowledge. Applied mathematics is broadly subdivided into three parts- applied analysis, approximation theory and applied probability. These categorizations are made complex due to the changes in mathematics and science over time. Numerical analysis, algebra, logic, decision theory, financial mathematics are some of the areas of mathematics which are widely applied to the domains of scientific computing, actuarial science, computer science and mathematical economics. This book discusses the fundamentals as well as modern approaches to the field of applied mathematics, and its various principles and techniques. Students, researchers, experts and all associated with applied mathematics will benefit alike from this book.