A chemical nomenclature Nomenclature is a series of principles for naming chemical substances in a structured manner. The International Union of Pure and Applied Chemistry (IUPAC) designed and modified the nomenclature that is most often used around the globe. The Blue Book and the Red Book are two books that provide the IUPAC's standards for identifying organic and inorganic substances, accordingly. The Green Book, a third book, outlines the guidelines for the use of signs for quantitative values (in collaboration with the IUPAP), and the Gold Book, a fourth publication, includes explanations of several scientific words used in chemistry. Biochemistry (the White Book, in collaboration with the IUBMB), analytical chemistry (the Orange Book), macromolecular chemistry (the Purple Book), and clinical chemistry (the Purple Book) all have comparable compendia (the Silver Book). These "color books" are reinforced by brief suggestions for particular situations issued in the journal Pure and Applied Chemistry on a regular basis.