A Standard is a norm, convention, requirement, or typical protocol. The term may also refer to automobiles, mathematics, military, or music. There are different types of standards, such as technical, reference, primary, breed, learning, language, care, gold, and many more.

A technical standard is a controlled artifact or similar formal means used for calibration. A technical standard can be developed privately or unilaterally, for example by a corporation, regulatory body, military, etc.Reference standards and certified reference materials have an assigned value by direct comparison with a reference base. A primary standard is usually under jurisdiction of a national standards body. Secondary, tertiary, check standards, and standard materials may be used for reference in a metrology system. A custom, convention, company product, corporate standard, etc., which becomes generally accepted and dominant, is often called a de facto standard. Standards can also be developed by groups such as trade unions, and trade associations. Standards organizations usually have more diverse input and usually develop voluntary standards: these might become mandatory if adopted by a government, business contract, etc.