During the era of the Human-Covenant War and the times both before and beyond it, warships often held the fates of worlds in their hands. The defenders and attackers on a world's surface, no matter how powerfull, no matter how brave or zealous, could be beaten, not through any action of their opponents on the ground, but fire rom above. Due to this, both humanity and the Covanant spent significant resources on their grand fleets of warships, from the small patrol ships and corvettes, to the relentless destroyers and frigates, to the grand and powerfull battleships and supercarriers.

Fighters:

Small, nimble, and packing significant firepower fir their size, fighters are one of the main striking arms of any fleet, providing an attack vector beyond even the range of MACs and Plasma Lances. Fighters also provide a more percise angle of attack, able to strike at spacific subsystems on a vessel when a long range volly can baraly ensure the ship is hit at all.

The main flaw of fighters are their lack of range. Even the most long legged strike craft lacks a slipspace drive, making them unable to move beyond t a single system or even planatary orbit without outside assistance. This assistance comes in the forms of most larger warships and even some middiling or small ones, but the majority of a fleet's strike craft are held and coordanated by carriers, which can hold dozens or even hundreds of the craft.

During the war, the effectiveness of fighters was greatly limited by the rapid nature of most battles, in most engagements, one side was already destroyed before any fighters could reach the opposing force, leaving them with limited use in large battles. Protracted campaigns and skirmish actions were where fighters truly got to shine, especally for humanity. Allmost as many Covanant warships were lost to fighter attacks from surface bases as fell to UNSC naval action, though avraging far lower in tonnage.

Patrol Ships:

Small vessels often lacking any firepower of note, patrol ships are a broad classifacation that technically incompasses a number of small vessel types used by both UNSC and Covanant forces. Patrol ships are used to patrol space at a more civilian level than most warships, more focused on smuggling and civilian safety than defense against any true armed force beyond maybe some lesser pirates. Many patrol ships lack any armament to speak of, though many do have smaller weapon systems.

Few of these craft served in the war outside of the most desperate of cercenstances. Covanant patrol ships were nearly unknown to mankind until after the war due to being unused by its invading forces.

Fast Attack Craft:

Fast attack craft, or FACs, sit between the realm of true warships and lesser craft, not truly belonging to either. Far more powerful than any fighter, yet having a far greater range and price, FACs see rare service for the major powers of the galaxy, used either for minior actions where even a corvette is unneeded, or in small squadrons to swarm larger ships. Where they truly shine, however, is in the hands of lesser groups. Pirates and insurrectionists can purchase, convert, or even build FACs far more easily than they could any true warship, while providing the firepower to take on any civilian threat they could face, or even small warships when used in great numbers.

Corvettes:

The smallest vessels truly considered warships, corvettes rarely see use in fleet actions on the scale of larger warships outside of some specalist vessels, more often being used for auxiliary duties like patrol and even exploration.

Most corvettes arent multi purpose like many larger warships, insted specializing in a spacific role such as point defense or electronic warfare and focusing its resources on that one role. Generalist corvettes do exist, but they are rarely the designs that see combat.

Frigates:

Swift, somewhat fragile, but heavaly armed for their size, frigates often serve in wolfpacks to protect larger vessels or hunt them down when used in combat. Outsude of fleet engagements, frigates are versatile vessels used for countless roles, from patrol, to troop transport, to fire support.

During abd after the war, frigates were the main warships of the UNSC, their big punch and low cost allowing them to do more damage for their price than any other ship type, while being quick to replace when they were destroyed. While this was tactically and strategically sound, it had a horrendus effect on both UNSC crew experience and morale, many dying as countless frigates are lost with all hands and people are forced to watch single Covanant ships cut through twenty time their number in frigates. The Covanant doesn't use frigates as prolifically as the UNSC, but they were still a common sight in support of larger vessels.

Frigates are the smallest ships that are generally expected to have at least one heavy weapon such as a MAC or Plasma Lance.

Destroyers:

Better armed and armored than their smaller frifate counterparts, destroyers were once the wain fleet warships of the UNSC, and remained in that role for the Covanant till its end. More expensive than their small counterparts, destroyers are far better combatants than frigates when dacing a pier opponent. This was not thr case for the UNSC, which lost destroyers at a rate similar to its frigates while they costed far more. This led to the UNSC shifting towards frigade production, with only light destroyers being produced through the war. Covanant destroyers retained their position, with many remenant forces continuing to use the vast destroyer fleets of the Covanant long after its death.

Cruisers:

The smallest of the capital ships, cruisers are a significant improvment over smaller vessels, with powerful weapons, significant ground and air complaments, and large flag facilities being common.

Cruisers can be deployed alone in high threat areas, being powerful enough to not need escorting, yet inexpensice enough to not be a major asset by itself. Nontheless, they are more often deployed at the head of a flotilla of smaller ships, or as part of a powerful squadron of other capital ships.

Both the UNSC and Covanant groups have a focus on cruisers due to their ballence of effectiveness and price, making them rather common compared to other large warships.

Battleships:

A rare breed of vessel with significant offensive firepower, battleships operate as parts of major fleets to privide heavy fire suppor. Their lack of versatility make them unpopular among militaries.

Carriers:

Massive warships that, while being heavaly armed, armored, and carying significant fighter contingents, provide their most vital service to any fleet through their command and logistical support facilities. Large storhouses and manufacturing facilities onboard provide everything an expeditionary force could ever need, while the massice command facilities on board allow an Admiral or Fleet Master to coordinate campaigns across an entire star system or even sectors of space.

Carriers are never deployed alone, having at minimum a battlegroup surounding them at all times.

Carriers can very greatly in size, with some light carriers being smaller than cruisers, while others can be far, far larger.

Assault Carriers:

A type of carrier specializing in planatary assault or support, assault carriers carry large armies and the facilities to support them.

Assault carriers are not as effective for space combat as standard carriers, but they can still be dangerous.

Supercarriers:

The largest vessels deployed in the galaxy outside of Forerunner or other ancient vessels, supercarriers are designed to command entire campaigns and theaters across vast expases of space, while also providing grand firepower for any fleet it is in. Few supercarriers are produced, each requiring a colossal amount of resources, but they are still worth the cost.