See also RFC 2119 that disambiguates the meaning of "must", "shall", "may" and others in specs. It's because of that RFC that you often see those words in caps

See also RFC 2119 that disambiguates the meaning of "must", "shall", "may" and others in specs. It's because of that RFC that you often see those words in caps in a spec. https://www.ietf.org/rfc/rfc2119.txt https://www.ietf.org/rfc/rfc2119.txt