Warhammer Online What Instanced battle means?

Can someone clarify this a little? How come that they call it an instanced battle if anyone who comes in can join the fight? How is it instanced then? Maybe I don't get the meaning of the word "instance" used in this context, or maybe they're just talking out of their collective asses.

[quote]Can someone clarify this a little? How come that they call it an instanced battle if anyone who comes in can join the fight? How is it instanced then? Maybe I don't get the meaning of the word "instance" used in this context, or maybe they're just talking out of their collective asses. [/quote]

Or maybe you're just overly critical and needlessly hostile? Who told you that anyone can join in? If it's instanced, it means it's for you and your group/guild/whatever and nobody else.