A good place to start is to read the introduction chapter of the NFSv4.0 RFC: https://tools.ietf.org/html/rfc7530

Further minor versions add other things that could be useful for cloud usage, e.g. in NFSv4.1 (https://tools.ietf.org/html/rfc5661 ) parallel data access, sessions, improved delegations, and in NFSv4.2 (https://tools.ietf.org/html/rfc7862 ) server-side clone/copy, sparse file support.