The jeep's main role is that of transportation. It can be customized for speed to quickly get into enemy controlled territory and then get out, or it can be lightly armored for a light combat role. Jeeps are the cheapest vehicle, and therefore, are the least resistant to damage.
APC
The APC's role is for the safe carriage of infantry through hostile territory. It is lightly armored but more resiliant to attack than the jeep while generally sacrificing speed. However, it can be customized for greater speed by stripping any defensive weaponary and installing a better engine. It can also possess the special ability of allowing units within a squad to respawn from their designated APC so long as their are remaining unused units in the APC and the squad has not been wiped out.
Light/Medium/Heavy Tank
The tank is the general purpose vehicle of the New Empire era. All tank versions use tank treads for greater mobility and feature either one or two cannons for the firing of tank based projectiles. They are more heavily armored than the APC with the heavy tank chassis being most heavily armored. Custom options allow for greater anti-infantry defenses such as reactive armor and a topside machine gunner but will ultimately still be susceptible to anti-armor infantry weapons from close range.
Artillery Tank
The artillery tank is designed for the role of striking an enemy position from great distances without fear of direct and immediate retaliation. The artillery tank features a main cannon capable of sending a mortar based round great distances. It can be customized for a small defensive weapon such as anti-infantry gun, but it is very susceptible to all forms of anti-tank weaponary. It should be utilized from a defensive position and in multiples for maximum effect.
Anti-Aircraft Tank
The anti-air tank is capable of providing a blanket of security to ground units from an airborne based attack. It utilizes a multitude of missile types from heat-seeking to radar guided for the efficient targeting and elimination of aircraft based threats. It can't equal the protection afforded by air superiority but is capable of severly increasing the surviveability of an entirely ground based squad which has no air support. It also has the ability to utilize its weapons on other ground based units and is not solely restricted to aircraft.