An application-layer protocol used for the distribution, retrieval, and posting of articles on Usenet newsgroups. Developed in the mid-1980s, NNTP was designed to replace the older UUCP (Unix-to-Unix Copy Program) system, which required point-to-point dial-up connections and was less efficient for growing global networks. By operating over TCP/IP, NNTP enabled faster and more reliable sharing of news articles across interconnected servers.
At its core, NNTP works in a client-server model. Servers exchange newsgroup content with one another, ensuring that articles propagate widely across the distributed Usenet system. Clients—such as newsreader applications—connect to NNTP servers to browse available newsgroups, download articles, or post their own contributions. Commands and responses are exchanged as plain text, making the protocol straightforward but powerful for handling large volumes of messages.
Although the popularity of Usenet has declined with the rise of the web, NNTP remains in use today for niche communities, private discussion boards, and even some content distribution services. Modern implementations often incorporate security features such as SSL/TLS encryption and authentication, which were not part of the original specification.
The significance of NNTP lies not only in its role in Usenet but also in its influence on how online discussions evolved. It set patterns for message threading, group-based discussions, and decentralized content distribution that shaped later technologies, including forums, mailing lists, and even aspects of social media.