NNTP, or Network News Transfer Protocol, is a protocol used for the distribution, inquiry, retrieval, and posting of Usenet articles. It allows users to read and post messages in newsgroups, which are organized discussions on various topics. Developed in the late 1980s, NNTP enables efficient communication over the internet by allowing multiple users to access and share information simultaneously. It operates over the TCP/IP protocol, ensuring reliable data transmission. Users typically access NNTP through newsreader software, which connects to NNTP servers to fetch and send messages.