An NNTP (Network News Transfer Protocol) server is a server that handles the transfer of newsgroup articles between Usenet servers and client newsreaders. NNTP is used for distributing and exchanging text-based content in a news format. NNTP servers host and deliver discussions and conversations within newsgroups, allowing people to post messages and send replies to others within the same newsgroup. The NNTP protocol is one of the most popular methods of transmitting Usenet newsgroups to users.