Аннотация:Modern protein science is broadening horizons by moving toward the systemic description of proteins in their natural habitats. This implies a transition from a classical reductionist approach associated with consideration of the unique structure and specific biological activity of an individual protein in a purified form to studying entire proteomes and their functions. This minireview provides a brief description of structural, functional, and expression proteomics, the dark proteome (or unfoldome), and some of the tools utilized in the analyses of proteomes.