This area is definitely unfinished.
Don't be surprised to find 404 pages.

ChatZilla Object Model Documentation

Classes

Object	Summary of functionality
PrefManager	Provides structured access to the application's preferences.
IRCClient	Represents the actual client itself. This is a singalton object. Provides a list of networks, and means to control/configure the client GUI.
IRCNetwork	Represents an IRC network - a collection of servers which are all linked, any one of which will access the same collection of users and channels.
IRCServer	Represents a single IRC server.
IRCChannel	Represents a single IRC channel, on a particular server. Stores and manages things like the channel topic, whether the user is currently in the channel, and the member list. Also provides means to talk on the channel, change the topic, and generally interact with it.
IRCUser	Represents a single IRC user, on a particular server. Stores and manages things like their nick (obviously!), hostname, description, and provides methods to send various messages to the user.
IRCChanUser	Represents a single IRC user as a member of a single channel. Stores and manages their per-channel state, such as whether they are oped or voiced.

Comments, suggestions, errors, ommissions, death threats, etc., to James Ross.