Python is an interpreted, object-oriented, high-level programming language with dynamic semantics. The high-level built-in data structures of python combined with dynamic typing and dynamic binding can be efficiently used for rapid application development (RAD). The simple and easy to learn syntax of Python significantly draws attention on readability. This aspect greatly helps in reducing the cost of program maintenance. There are several applications of python such as language development, prototyping, database access, software development, and graphic design. Python supports modules and packages, which encourage modular programming and code reuse. The simple and versatile nature of Python makes it a powerful tool in scientific and engineering computations. The data and numerical analysis as well as the plotting libraries of python such as NumPy, SciPy and matplotlib have become very popular programming tools in industry and academia. This book outlines the importance of Python as an important computer language for solving numerical problems. It will serve as a valuable source of reference for graduate and post graduate students.