Here is a cheat sheet of essential IRC (Internet Relay Chat) commands, which are typed in the chat input area starting with a forward slash (/).
 
Basic Commands
These commands are fundamental for navigating and communicating on IRC networks. 

    /join #channel - Joins the specified channel. (#ebooks, #bookz)
    /part [#channel] [message] - Leaves the specified channel. If no channel is specified, you leave the current window's channel.
    /quit [message] - Disconnects from the current server with an optional leaving message.
    /server hostname - Connects to the specified IRC server.
    /nick nickname - Changes your nickname to the one specified.
    /list - Displays a list of all public channels on the current network.
    /msg nickname message - Sends a private message to a user without opening a new chat window.
    /query nickname [message] - Opens a private chat window with the user and optionally sends a message.
    /me action - Displays an action message, e.g., "YourName action".
    /whois nickname - Shows detailed information about the specified user (e.g., hostmask, idle time, server info).
    /away [message] - Sets your status to "away" with an optional message. Running it again removes the status. 

Channel Operator Commands
If you have operator status (op, typically indicated by a @ symbol next to your name), you can use these commands to moderate a channel. 

    /mode #channel +o nickname - Gives a user operator status in the channel.
    /mode #channel -o nickname - Removes operator status from a user.
    /kick nickname [reason] - Forcibly removes a user from the channel with an optional reason.
    /mode #channel +b user_address - Bans a user from the channel. The user address is often in the format nick!ident@hostmask.
    /mode #channel -b user_address - Unbans a user.
    /topic #channel new_topic - Sets the channel's topic.
    /mode #channel +m - Sets the channel to moderated mode, allowing only opped or voiced users to talk.
    /mode #channel +i - Makes the channel invite-only.