An IRC server is a computer system that facilitates real-time text communication over the Internet using the Internet Relay Chat protocol. It allows users to connect and join various channels, where they can chat with others in groups or privately. Each server can host multiple channels, enabling diverse discussions on various topics. Users connect to an IRC server using a client application, which provides an interface for sending and receiving messages. The server manages the connections, ensuring that messages are delivered to the appropriate channels and users. This setup allows for a dynamic and interactive online community.