Hello,
I played TBC and WotLK back in the days. On a RP-PvP realm.
I remember that the global chat channels were mostly well used. But it doesn’t seem to be the case nowadays and a non-negligeable amount of people lack knowledge about some of the channels functionnalities.
Please, correct me if I am wrong, since I might be misremembering.
-: General chat (usually /1) is local to the zone you are in. If you are in Dun Morogh, everyone in Dun Morogh can hear you.
-: Trade chat (usually /2) is local to EVERY capital city and nothing else. Thus it is not the best way to advertise for your LFG needs, but more on this later.
-: Local Defense chat (usually /3) is local to your current zone, and possess a system that automatically announce attacks on settlement’s NPC.
And now for the “offcial yet not opened by default” channels. You can see these channels in the settings of your chat window (as well as change numerous things like chat colours):
-: LookingForGroup (usually /4) is a WORLD GLOBAL channel. Everyone from Tanaris to Undercity to Dun Morogh to Stormwind to GM Island will see your message here (as long as they are in your faction ofc). Since this chat is dedicated to LFG and global, it’s the best for that. Plain and simple.
-: Any other channel you decide to manually create is world global.
-: LFG is not an “official” channel, but many people use it nonetheless. Because typing /join LFG is so much simpler than /join LookingForGroup. It is, also, global.
So if you want to create a channel named SecretSocietyOfPeopleHatingGnomes, you can do so and it will be global. You can even set passwords to channels if you wish to. But I suggest you read the in game help about channels if you wish to know more.
/help
/chathelp
It can be VERY useful for planning world events for example (RP or PvP). Open a channel with moderator rights and invite everyone wanting to participate in your event.