Units

Even though it doesn't display in game, Starfire's units have fractional speed differences. Thus a Ver 3 Infantry division is faster than a Ver 3 Infantry division.

Researching new Infantry models gives the associated models for Marines, Mountain, Motorized, Militia and Garrison units assuming you also know the appropriate enabling technologies.

Infantry - the mainstay of virtually all armies. These represent a "generic" division of roughly 17,000 men in the field.

Marines - the best unit for making amphibious assaults. Marines also have some advantages attacking across rivers and in swamps and jungles. Marines are "elite" units and man for man have more firepower.

Militia - cheap hastily raised units. Militia can't stand up to professional military units but if you have plenty of manpower they can be a cheap defense to slow down your enemy. In Starfire Militia "divisions" are half division size.

Motorized - infantry units with truck transport. As the war progresses and you research the appropriate technology, motorized units become more and more motorized and hence gain speed.

Mountain - these are "light" infantry, a smaller division (13,000 men in the field) with advantages in hilly and mountain terrain. Due to extra training these are "elite" units and man for man have more firepower.

Garrison - these are infantry units without transport (in the game they can only move via strategic redeployment). Starfire's garrison units are sized as "Regiments" (roughly one third of a division). Garrisons are destroyed if forced to retreat.

Paratroopers - these are airborne assault units, sized as roughly one brigade it would require three of these to equal a division. Paratroopers are elite soldiers.