1) A soldier from Star Wars. This type of soldierwore white armor vaguely reminiscent of the human skeleton. The Stormtroopers had many different versions of armor, ranging from forest troopers to desert troopers. The Stormtroopers were commanded by the evil Empire.
It is rumored that all Stormtroopers are clones, remnants of the great Clone Wars.
2) Stormtroopers are considered, within the storyline of the movies and other fan works, to be extremely precise when shooting. This theory is disproven to the audience /many/ times over. The characters never seem to figure it out, though.
1) Random Stormtrooper picks up a part, and holds it up for his commander to see. "*click* Look sir. Droids. *click*"
2) Obi-Wan, pointing at a blasted hull of a transport: "Only Imperial Stormtroopers are so precise"
It appears as aroughly 300' robot, with a single cyclopticsearch eye. The design is fairly reminiscent of WWII Germany's soldiers. The typical soldier's Zaku is green, high ranking officers, however, have been known to have blue or light red colorations (see Char Aznable).