The intent of defining a list of tools as “Standard” is to provide uniformity in manufacture, integrity, and use. This “uniformity” allows for ease of service, and provides interchangeability of common parts for the user, and ultimately for the consumer. It is also meant to assure quality of function for which the thread is intended.
In the United States, there are three primary organizations that contribute to those definitions. The descriptions of the entities below are meant to be simple for the purpose of illustration to show basic scope of involvement.