Proteins are large biomolecules or macromolecules that are made of long chains of amino acid residues. The entire set of proteins that are produced by an organism is called the proteome. It differs from cell to cell and also varies with time. A cell makes different proteins at different times and conditions, such as during cellular differentiation, carcinogenesis, cell cycle and development. The study of proteins is covered by the discipline of proteomics. This field has evolved tremendously due to the development of many innovative approaches. The common techniques for the study of proteins are mass spectrometry and protein profiling, reverse-phased protein microarrays and protein chips. This book brings forth some of the most innovative concepts and elucidates the unexplored aspects of proteomics. Different approaches, evaluations, methodologies and advanced studies have been included herein. The extensive content of this book provides the readers with a thorough understanding of the subject.