WoW Tips to Hotkeys

TARGETING

Cycle through enemies in front of you: Tab 

Cycle back through enemies in front of you: Shift & Tab 
Cycle through friendlies in area: Ctrl & Tab 
Cycle backwards through friendlies: Ctrl & Shift & Tab 
Target self: F1 
Target party member: F2-F5 
Target pet: Shift & F1 
Target party member's pet: Shift & F2-F5 
Attack target: T 
Target last hostile: G 
Have pet attack target: Shift & T 
Assist: F (you attack the same target as a selected ally is attacking) 
Show name plates: V 

CHAT COMMANDS/FUNCTIONS 

Open chat box: Enter 
Switch to Say mode: /s in chat box (you will be heard close to you) 
Whisper: /w [playername] or /t [playername] (private message) 
Party Chat: /p 
Guild Chat: /g 
Reply to last private message: /r 
Yell: /y (you will be heard in whole zone - use sparingly!) 
Enter General Chat: /1 
Enter Trade Channel: /2 (in capital cities only) 
Enter Local Defense Channel: /3 
Enter Looking for Group Channel: /4 
Enter World Defense Channel: /5 (open to PvP ranks 11+) 

INTERFACE PANEL COMMANDS

Open/close Character Panel: C
Open/close Backpack: B or F12 
Open/close other bags: F8-F11 
Open/close all bags: Shift & B 
Open/close Spellbook: P 
Open/close Abilities Book: I 
Open/close Pet Book: Shift + I 
Open/close Pet Panel: Shift & P 
Open/close Reputation Panel: U 
Open/close Skills Panel: K 
Open/close Honor Panel: H 
Open/close Talents Panel: N 
Open/close Quest Log: L 
Open/close World Map Panel: M 
Open/close Social Panel: O

Note: In World Map, by pressing M you first get a detailed map of the zone you are in, then again will zoom out to give you a map of the continent, and once more will take it to a world map. 

Note: The Who tab allows you to search for players by player name, class, race, zone, guild and level. Also by typing /who [playername] you can see if a particular player is logged on - their level, name, race, class, current zone and guild affiliation will appear in your chat log. 

Note: Friends List allows you to add names of players you chat to or want to deal with regularly - this can include your other characters if you wish to mail them. From here you can invite friends to your parties and raids or select them to whisper to them. 

Note: Ignore List is basically the opposite - put people here you don't wish to hear from again!