I didn't know this, but thought it might be helpful for setting up macros (from the manual...I'm bored):


[align=left]Spell and ability icons have a background color to designate targeting:[/align]
[align=left]
BACKGROUND = AFFECTS
Red = a single enemy target.
Blue = all non-player creatures within range.
Green = all enemies within a target encounter.
Yellow = only the caster.
Gold = a single targetted group member.
Purple = all members within your group.
[/align]
[align=left]Thought I'd share. :P [/align]