Written for graduate students, researchers, and professionals in the field of materials modeling, this reference provides a concise description of coarse graining. It reviews a broad range of approaches and methods used in the field and offers hands-on, practical information. Chapters describe what coarse materials are used for, when and how to use them, how to analyze their data, and how to test sanity and reliability. This reference connects the fundamental background and theory of coarse graining to its implementation and use in real-world problems.