The command varies from server plugin to server plugin cause some people make they're one plugins
To answer a faction invite just do /f join <faction name>
You use /f leave [faction name]
If you are in a faction, and want to teleport to your faction home, just type /f home.
I assume you're talking about a faction invite. the command is /f join <faction>
add them to your faction with /f join <faction name>
Press T
You will need to the faction plugin for bukkit once running then do in the chat /f create {name of faction here}
You kill mobs and players
description
someone who moderates the factions
You pretty much said it yourself. It's /f disband [faction tag]
Factions are kinda like groups or colonies in Minecraft. I'm in a faction on one server called PIEmasters (even though I hate pie >:D).