znc is an IRC proxy. It runs as a daemon and connects to IRC server, then allows you to connect from a workstation and work as the user that is logged in to the IRC server. After you disconnect, it maintains the connection to the server.
soju is a user-friendly IRC bouncer. soju connects to upstream IRC servers on behalf of the user to provide extra functionality. soju supports many features such as multiple users, numerous IRCv3 extensions, chat history playback and detached channels.
