According to the suggested title of the current book, this book is residing in the applied bioinformatics field. It means that it has been designed from the perspective of an end-user who wants to act on the available web based bioinformatics databases and tools for computational molecular genetics analysis. The missense variants were selected because it is the most abundant variants. This book will be mannered in consecutive three levels, where the first level is almost indeed for beginners. The targeted readers of this book could include any geneticist who wants to know the different approach and algorithms which considered in common bioinformatics tools. Also a student who has a basic molecular biology background in basic molecular is included. The book's headings were been started with knowing of some main differential concepts to elucidate the fine barriers between them. In this book, I mainly aimed to acquire basic background, nevertheless it's updated later. The followed updates will be discussed in the higher levels.