Moderated and unmoderated newsgroups

A minority of newsgroups are moderated, meaning that messages submitted by readers are not distributed directly to Usenet, but instead are emailed to the moderators of the newsgroup for approval. The moderator is to receive submitted articles, review them, and inject approved articles so that they can be properly propagated worldwide. Articles approved by a moderator must bear the Approved: header line. Moderators ensure that the messages that readers see in the newsgroup conform to the charter of the newsgroup, though they are not required to follow any such rules or guidelines. Typically, moderators are appointed in the proposal for the newsgroup, and changes of moderators follow a succession plan.
Historically, a mod.* hierarchy existed before Usenet reorganization. Now, moderated newsgroups may appear in any hierarchy.
Usenet newsgroups in the Big-8 hierarchy are created by proposals called a Request for Discussion, or RFD. The RFD is required to have the following information: newsgroup name, checkgroups file entry, and moderated or unmoderated status. If the group is to be moderated, then at least one moderator with a valid email address must be provided. Other information which is beneficial but not required includes: a charter, a rationale, and a moderation policy if the group is to be moderated. Discussion of the new newsgroup proposal follows, and is finished with the members of the Big-8 Management Board making the decision, by vote, to either approve or disapprove the new newsgroup.
Unmoderated newsgroups form the majority of Usenet newsgroups, and messages submitted by readers for unmoderated newsgroups are immediately propagated for everyone to see. Minimal editorial content filtering vs propagation speed form one crux of the Usenet community. One little cited defense of propagation is canceling a propagated message, but few Usenet users use this command and some news readers do not offer cancellation commands, in part because article storage expires in relatively short order anyway.
Creation of moderated newsgroups often becomes a hot subject of controversy, raising issues regarding censorship and the desire of a subset of users to form an intentional community.