Proteomics is the large-scale study of proteins, particularly their structures and functions. Proteins are vital parts of living organisms, as they are the main components of the physiological metabolic pathways of cells. Proteomics is an interdisciplinary domain formed on the basis of the research and development of the Human Genome Project it is also emerging scientific research and exploration of proteomes from the overall level of intracellular protein composition, structure, and its own unique activity patterns. It is an important component of functional genomics. Proteomics is the large-scale functional analysis of proteins extracted from intact organisms, tissues, individual cells, or cell compartments, at defined time points during development or under specific conditions. Plant Proteomics highlights the rapid progress in this field in plants, with emphasis on recent work in model plant species, subcellular organelles, and specific aspects of the plant life cycle such as signaling, reproduction and stress physiology. Proteomics generally refers to the large-scale experimental analysis of proteins; it is often specifically used for protein purification and mass spectrometry. Proteomics is the next step in the study of biological systems. It is more complicated than genomics because an organism's genome is more or less constant, whereas the proteome differs from cell to cell and from time to time. Distinct genes are expressed in different cell types, which mean that even the basic set of proteins that are produced in a cell needs to be identified. Proteomics has been defined as “the systematic analysis of the protein population in a tissue, cell, or subcellular compartment”.