The central aims are: elucidation (by experimental methods) of structural features of the biological entities (proteins, nucleic acids, etc.), application of computational tools and approaches to study of information content, organization, and processing in biological systems, application of medical and health data at the molecular level (biomedinformatics), annotation of structural and chemical characteristics in molecular and drug design (cheminformatics). Thus, it requires trans-disciplinary collaboration between biophysicists, drug chemists, molecular biologists, biomedical and computer-aided modeling experts. Acquisition of high-throughput biological data (e.g. from the genomic projects) at fast rate has ushered in computer-intensive data analysis (in silico analysis). But, considerable 'algorithmic' complexity of biological systems requires a vast of amount of detailed information (experimental and computational) at the cellular and molecular levels for their complete description. Therefore, there is a need for books in this subject with due emphasis on both experimental as well as computational aspects. With these broad objectives in mind, the material contents of this book are organized under-molecular biophysics, experimental methods of structure elucidation, database search, data mining and analysis, computational methods of structure prediction, and rational molecular/drug design (molecular engineering) and validation, with easy interface between these areas and various chapters. Ample tables and figures are intended to facilitate the readers an insight to the structure-function features at the molecular level. Exercise modules and bibliography for each chapter, and glossary are aimed at providing the reader wider perception and insight to the subject matter, and scientific and technical terms. Index is provided to help an easy access to the words and topics to the subject matter.