Is there any authoritative description of the imperial rank titles and their insignia in SW? I would imagine that they broadly correspond to real world military ranks, but some accounts place 'commander' above 'captain', which doesn't seem right as it wouldn't be the case in any real world naval force. Also what about the Stormtroopers? Do their rank structures correspond to real world army (or perhaps marines) ranks? Some stormtrooper officers are addressed as 'commander' but whether that is a formal rank is unclear. In the real world there are Commanders in the Navy but not the army, where the equivalent rank is Lieutenant-Colonel. Do they have identifying indicators of rank when in armour? The coloured shoulder pads sometimes seen don't seem to give away much. I wondered if stormtrooper armour might have some device built in that identifies rank to other imperials but that is not visible on the surface. There's one point where a scout trooper addresses another as 'sir' and salutes, indicating that the latter is an officer, even though there is no difference in their costume, as far as I can notice.