With the decoding of whole genome sequences of many organisms, new vistas of research have emerged in computational biology. The scientific community has free access to the genome sequence data from the public databases. Many times, it is really hard to make sense of these huge data of DNA and protein sequences. Therefore, bioinformatics tools are used to handle, store and analyze genome sequence data for the benefit of mankind. The book has been written in a simplest possible manner so that every one should understand the basic concepts of genome sequence analysis and bioinformatics. The book is structured in such a way so that readers should first know about how whole genome sequences are generated by using high throughput DNA sequencing technologies and then storing of sequences in biological databases. Second part deals with the basic principals involved in sequence analysis and applications of softwares along with practical exercises. Thirdly, data mining approaches for the discovery of genes and DNA markers have also been discussed. Besides, glossary of important terms and introduction to basic bioinformatics softwares has been included for the benefits of readers. The book will serve as a text book to the B. Tech (Bioinformatics & Biotechnology) students and would also be useful reference book to the postgraduate students and research scientists working in the areas of life sciences, genomics, biotechnology and molecular biology as well as Masters in Computer Applications (MCA) who are interested in bioinformatics.