CARRIER CLASS

Huge ships that are mostly responsible for planetary Marine deployment and carrying large amounts of Longsword Fighters and Pelican drop ships.

Examples of Carrier Class ships include: Musashi, Atlas, Magellan, and Trafalgar (Super Carrier).

CRUISER CLASS

The most strongest ship class to be made by human hands, but also the most costly and timely to build. Only twenty remain in the entire fleet, perhaps less. All Cruisers are being pulled back to guard the remaining Inner Colonies.

An example name of Cruiser Class ships is, Hermes II,  Leviathan, Basra, and Hannibal. 

DESTROYER CLASS

A very strong Class with thick, all round Titanium-A armor and a strong compliment of Archer missiles and Shiva Nuclear Warheads. Not to mention a MAC Cannon. 

Example names of Destroyer Class ships include: Iroquois, Minotaur, Herodotus, Pioneer, Resolute, Lancelot, Basra, Hercules, Heracles, and Gettysburg. 

FRIGATE CLASS

The most common type of UNSC vessel, armed with a standard MAC cannon and Archer missiles. 

Example names of Frigate Class ships include: Meriwether Lewis, Midsummer Night, Fair Weather, Gorgon, Vastok, Commonwealth, Arabia, Alliance, and Allegiance. 

HALCYON CLASS CRUISER

The only noteworthy design feature of the Halcyon Class Cruiser is her internal superstructure. The structural system was designed by Doctor Robert McLees (co-founder of the Reyes-McLees Martian Orbital Shipyards). It was, at that time, deemed unnecessarily over-massed and costly due to a series of cross-bracings and interstitial honeycombs. The design was subsequently dropped from all further production models. The Pillar of Autumn and 10 other vessels were the only ships-out of 50-to be built with this type of superstructure.

Names include, Dawn Under Heaven and Pillar of Autumn. 

The UNSC Cruiser Pillar of Autumn is a Halcyon-class cruiser, pulled from long-term storage in 2550 to server as an emergency ship in the Zeta Doradus Theater of Operations.
The Pillar of Autumn is armed with Shiva nuclear-tipped missiles, Archer Missile pods, a prototype MAC gun, and a full complement of fighter craft, and Marines.

It has extra Titanium A armor, secret Archer Missile Pods within its armor, concealed 500mm auto cannons on its underbelly and a triple round MAC cannon. The Pillar of Autumn was the first vessel to have the latest reactor model enabling it to increase standard power by 300%.

ONI STEALTH CLASS

ONI stealth ships are known as prowlers. They are very sleek in design compared to other bulky human vessels and they have angled black stealth surfaces which make it almost invisible in space as they appear as black moving on black. Most, if not all ONI ships are defenseless. 

ONI Stealth ships take on innocent sounding names like: Circumference, Applebee, Chiroptera and Lark.

REFIT STATION

Huge Space Stations, described as large metal squares. Capable of repairing, rearming and refitting several UNSC ships at once due to its colossal size. Also able to move like other ships and not restricted to the Gravitational pull of planets which is why the Cradle was able to move and save several UNSC ships from a Plasma Torpedo bombardment by acting as a human shield for the defenseless vessels.  

An example of a refit station is, Cradle. 

SCOUT CLASS

A very small but agile ship, rarely seen in the thick of battle. Often used to check after battles for reports.

An example of a scout ship is, Argo.

SENSOR OUTPOST

Small outposts which use drones to constantly monitor real and slip space. Are used to see upcoming Covenant fleets so planets can be alerted in time to prepare. 

Names of sensor outposts include: Fermion, and Archimedes.