A standard is a document that provides requirements, specifications, guidelines, or characteristics that can be used consistently to ensure that materials, products, processes, and services are fit for their purpose.In layman's terms, you can think of a standard as an agreed-upon formula for the best way of doing something. 

A voluntary consensus standard is a type of standard developed or adopted by voluntary consensus standards bodies through the use of a development process characterized by openness, balance, due process, consensus, and the right to appeals.

Types of voluntary consensus standards include:■  Product/design-based standards, which identify specific design or technical characteristics of a product.■  Performance-based standards, which test products by simulating their performance under actual service conditions.■  Management system standards, ···

Consortia standards are voluntary standards whose development is generally initiated by groups of companies agreeing to work together to address a single commercial/market need. Participation is often limited to members of the consortia—historically heavily comprised of the interested companies, though some consortia have been expanding their membership structures to enable participation by government agencies, universities, and/or corporate end users (rarely individuals).

An international standard is a document that has been developed through the consensus of experts from many countries and is approved and published by a globally recognized body. It comprises rules, guidelines, processes, or characteristics that allow users to achieve the same outcome time and time again.Th···