In this book, we have considered different mathematical problems with their numerical methods. Moreover, we have discussed the iterative and absolute errors which arise from using these methods. In addition, the numerical codes for these methods, written in MATLAB, are presented at the end of this book.I believe that this book will be an excellent guide for undergraduate students at colleges of science and engineering, and it can help them to understand the course of numerical analysis easily. In addition, they can learn basically how to write computer codes for the studied numerical methods.