NNTP is not a particular software package, but an Internet standard described in RFC-977. It is based on a stream-oriented connection, usually over TCP, between a client anywhere in the network and a server on a host that keeps Netnews on disk storage. The stream connection allows the client and server to interactively negotiate article transfer with nearly no turnaround delay, thus keeping the number of duplicate articles low. Together with the Internet's high-transfer rates, this adds up to a news transport that surpasses the original UUCP networks by far. On the Internet itself, it is even within the range of minutes.
Various commands allow clients to retrieve, send, and post articles.
If the server wants the article, the client sends the article, terminated by a single dot on a separate line. Pulling news needs tight control by the server over which groups and distributions it allows a client to request. For example, it has to make sure that no confidential material from newsgroups local to the site is sent to unauthorized clients. There are also a number of convenience commands for newsreaders that permit them to retrieve the article header and body separately, or even single header lines from a range of articles. An overall problem of NNTP is that it allows a knowledgeable person to insert articles into the news stream with false sender specification.