The document outlines the key concepts of design systems, including their value and building blocks. It defines design systems as a methodology for designing products that includes objective design solutions implemented as reusable components, as well as abstract collaboration strategies and processes. The building blocks are categorized and include components, patterns, styleguides, pattern libraries, and component libraries. Their definitions and interconnections are described. The value of design systems is increased productivity and consistency for users, as well as reuse, communication of design, and ensured quality for teams.