There are three types of roles a soldier can have. Each squad will tend to specialize in one area.
Infantry- This is soldier type #1. It consists of your basic light/medium soldiers, medics, assault troopers, attack buggies and basilisks. Remember, this soldier type will always be the mainstay of the army. It will be infantry doing all the basic "grunt work." Also, this soldier type will have to exercise teamwork moreso than any of the others! The Defuncters are about sacrificing personal glories for the good of the mission. Besides, it's just a game.
Support- This is soldier type #2. They will consist of tanks, MAX armor, aircraft, combat engineers, and Galaxy dropships. They will be offering support to infantry in the form of air support, heavy weapons, repairs, and transportation. These troops are often not on the front lines like the Infantry class, but without them, we could not funtion! This is an integral part of any army.
Special Ops- This is last but not least, soldier type #3. They will be doing more of the secretive missions, like sabatoging an enemy structure or vehicle, for example. They will consist of infiltrators, snipers, hackers, assassins, and forward scouts. Often, they will be sent in before the main attack to soften up the enemy or scout out positions. They are the fleeting shadow in the corner of your eye, executing their operations secretly and without detection.