BCP 14 contains the following RFCs:
Abstract of RFC 2119
In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
Abstract of RFC 8174
RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings.
For the definition of Status, see RFC 2026.
For the definition of Stream, see RFC 8729.