Standards are documented agreements which contain technical specifications or other precise criteria used consistently as rules, guidelines, or definitions of characteristics, to ensure that materials, products, processes and services are fit for their purpose.
Scientific and professional organizations such as the ASTM, ASME, IEEE, trade organizations, and governments produce standards. In the United States, the American National Standards Institute (ANSI) coordinates many standards producing organizations. The International Organization for Standardization (ISO) is the world's largest developer and publisher of international standards.