M12 Chaingun Warthog
From Halopedia, the Halo wiki
Warthog is a generic term for a lineage of United Nations Space Command ground vehicles. It is affectionately known as the 'Hog by UNSC soldiers.
Introduction
The Warthog is the modern-day "Jeep": all of its variants are equipped with a seemingly full-time 4x4 transmission, the ability to turn its front and rear wheels to allow for tighter turning, and can carry 3 people; 1 driver, 1 gunner, and 1 passenger (with the exception of the Warthog APC, which can carry 11 passengers, as befitting with its classification). The driver has no forms of attack except ramming enemies with the Warthog itself, which instantly kills an enemy on foot in Halo: Combat Evolved. In Halo 2, factors such as speed and direction do not allow every ram to be a guaranteed kill. The passenger, or shotgun seat, is the worst spot to be in, it is very difficult to aim (made even harder in Halo 2 with the removal of the first person view in the seat) while the warthog is moving, and if you try to reload, you will automatically jump out if you hold the X button too long. The gunner stands on the back of the Warthog and uses that particular variant's main weapon, may it be a chaingun, gauss cannon, or rocket launcher.
A Warthog variant is set to be a vehicle again for Halo 3.
Variants
M12 Warthog LRV
The M12 Warthog LRV (Light Reconnaissance Vehicle) is the most common type of Warthog, and is seen in Halo: Combat Evolved, Halo PC, Halo 2, and is slated to be in Halo 3. It mounts an M41 Light Anti-Aircraft Gun.
M12A1 Warthog LAAV
The M12A1 Warthog LAAV (Light Anti Armor Vehicle) is only seen on Halo PC, and mounts a rocket launcher.
Its role as the primary UNSC LAAV is usurped by the M12G1 Warthog LAAV in Halo 2.
M12G1 Warthog LAAV
Template:Mainarticle The M12G1 Warthog LAAV, seen in Halo 2 and slated to be in Halo 3, mounts a Gauss Cannon.
Warthog APC
The Warthog Armored Personnel Carrier is a United Rebel Front ground vehicle. It is essentially a M12 Warthog modified by the URF to include a passenger section capable of carrying troops and supplies.