Nearly 800 helpful files including FAQs, primers, technical guides, clients and scripts, and server lists and maps.

Contains links, explanations, guides, and many good documentations.

Resources for Undernet server operators.

UnderNet's IRC-related FAQ

Specifications for CTCP as well as DCC protocols which are now standard supplements of IRC.

Advanced reference of IRC commands.

Based on the chatting client, this is a good explanation on how to get started, easily. Contains plenty of other related links.

IRC Protocol