The following commands can be used in any chat channel; they can also be used during game setup or while a game is in progress.

/help - (e.g., /help whisper)
Displays usage help for chat topics.

/whois [user] - (e.g., /whois TPark or /whois #133115)
Provides basic information, including current location, on a user. This is an excellent way to find your friends online.
Usage: /whois #[number]
Aliases for this command : /where /whereis

/whoami - (e.g., /whoami) - displays your information on Battle.net.

/whisper [user] - (e.g., /whisper JohnS or /whisper #236325)
Sends a private message to a user online regardless of that user's current channel. This is an excellent way to let a friend know you are online.
Aliases for this command: /w /msg /m

/squelch [user] - (e.g., /squelch BFitch or /squelch #223251)
Ignores any future messages from that user, effectively muting that user to you.
Aliases for this command: /ignore

/unsquelch [user] - (e.g., /unsquelch BFitch or /unsquelch #223251)
Allows a previously squelched user to talk to you normally.
Aliases for this command: /unignore

/away [text] - (e.g., /away eating dinner)
Displays a message that you are away from your keyboard whenever someone whispers to you or does a /whois command on you. To disable this command, use /away again.

/dnd [text] - (e.g., /dnd sorry playing a game with GFraizer)
"Do Not Disturb" -- prevents ALL whispers from displaying on your screen. Use it like you would the /away command.
This will prevent people from sending whispers to you while in a game as well. You will still see all normal public channel messages. To turn DND mode off, just type /dnd and hit enter.

/who [channel] - (e.g., /who Open Tech Support)
Displays a list of all users in the given channel.

/stats [user] ID - (e.g., /stats DavidN STAR or /stats #42 STAR)
Displays that user's Win/Loss/Disconnect record for both normal and ladder games.

STAR - Starcraft
SEXP - Starcraft Expansion (Brood War)
W2BNE - Warcraft II Battle.net Edition

/users
Displays the number of users currently on Battle.net.

/time
Displays the current Battle.net time.

The following commands can only be used while in a chat room

/channel [channel name] - (e.g., /channel Blizzard Tech Support)
Switches you to a channel without requiring you to use the Join Channel screen.
Aliases for this command: /join

/me [text] - (e.g., /me is rolling on the floor laughing!)
Displays whatever descriptive text you enter. If PatN entered "/me is rolling on the floor laughing!" you would see "PatN is rolling on the floor laughing!"
Aliases for this command: /emote

The following commands can only be used by channel operators

/designate [user] - (e.g., /designate AlenL or /designate #423262)
If the channel operator had designated more than one person, the last person designated will have ops.
If the channel operator leaves the channel and has designated more than one person, the last person designated will have ops.

/resign
Step down as channel operator and become a normal user again.
Aliases for this command: /rejoin

/kick [user] - (e.g., /kick TwainM or /kick #234226)
Kicks a user out of the channel. This is best used as a warning, since a kicked user can return at any time.

/ban [user] - (e.g., /ban RobertB or /ban #137389)
Kicks a user out of the channel and prevents him or her from returning until the current operator steps down or leaves the channel. This is the most powerful command at an operator's disposal. Use it wisely.

/unban [users] - (e.g., /unban RobertB or /unban #137389)
Allows a banned user to return to the channel.

Shorcut Keystrokes

CTRL-X
Cuts the selected text

CTRL-C
Copies the selected text

CTRL-V
Pastes the selected text

CTRL-A
Selects all text

CTRL-N
Diablo II: Lord of Destruction: Pastes the name you have selected

ALT-N
Diablo, Starcraft, and Warcraft II BNE: Pastes the name you have selected

/d2notify
Diablo II: Lord of Destruction: Toggle channel enter/leave notifications

ALT-V
Diablo, Starcraft, and Warcraft II BNE: Toggle channel enter/leave notifications

ALT-W with user selected
Diablo, Starcraft, and Warcraft II BNE: Sends a private message to the selected user
Aliases for this command: /w /msg /m /whisper

TAB
Diablo II: Lord of Destruction: Cycles through the last 10 commands
Starcraft: Displays the last command, then cycles through the users in the current channel

CTRL-M
Diablo II: Lord of Destruction: Toggles music in Battle.net and the main menus on/off