From
Wookiepedia :
Snowtroopers were specialized stormtroopers of the Galactic Empire trained and equipped to operate in frigid environments such as the icy planet of Hoth. When the Empire routed the enemy Rebel Alliance from its headquarters on Hoth, snowtroopers led by Darth Vader were involved in the battle.
Snowtroopers were known to have been handpicked from worlds already known to have frigid climate. That way the Empire would have troopers that were already used to the cold climates they were going to be dropped into. A must have for their elite corp. The snowtrooper armor was also thermal to trap body heat to help defend against the cold.
From
Wookiepedia :
Scout troopers, also known as biker scouts, were specially trained soldiers of the Imperial Stormtrooper Corps. As light-armored variants of the Imperial stormtroopers, scout troopers were specifically trained for activities too complicated for regular infantry troopers. As such, they were exceptional additions to the Imperial Military as reconnaissance troops, spies and survivalists. They were especially excellent marksmen, and thus they were regarded as the finest snipers in service to the Galactic Empire. Hence, they were particularly useful as assassins.
Their wide-range of skills inevitably created feelings of pride and self-importance amongst the scout troopers. As a consequence of their bravado, they developed a fierce rivalry with their infantry counterparts, as well as everyone else in the military who was of equal or lower rank. Their most infamous activity was arguably in the Battle of Endor in 4 ABY. Although they were stationed in an environment most suited to their training, the scout troopers were unable to prevent a small team of Rebel soldiers from destroying the shield generator that protected the incomplete Death Star II. An entire legion of Emperor Palpatine's best soldiers, including many scout troopers, were annihilated by a few Rebels, assisted by the Ewoks, an indigenous species of Endor.
From
Wookiepedia :
Stormtroopers were the elite soldiers of the Galactic Empire. Like Imperial-class Star Destroyers and TIE fighters, stormtroopers served as ever present reminders of the absolute power of Emperor Palpatine. These faceless enforcers of the New Order were considered an extension of the Emperor's will, and thus they often used efficient yet usually unreasonable tactics as a way to keep thousands of star systems throughout the galaxy in line. At the height of the Empire, stormtroopers had effectively become symbols of major authority. With few exceptions, they were distinguished from all other military units by their signature white armor.
