Fleet CarrierA large carrier outfitted with multiple squadrons of aircraft including fighters, dive bombers, and torpedo bombers. Their large size and hangar space comes at the cost of armor, speed, and maneuverability. While normally outfitted with several secondary guns and multiple AA mounts, it is vulnerable to attack from any ship.
Support CarrierThis kind of carrier is outfitted with a large store of ammunition and fuel for both ships and aircraft, several as a refueling station for aircraft closer to the area of engagement. Since these kind of carriers are closer to the front, they are outfitted with heavier armor and secondary weapons.
Escort CarrierA small-scale and cheaper version of the fleet carrier, these ships are designed primarily for guarding important shipping routes and smaller engagements. Their lower tonnage means that they are faster and more maneuverable than their bigger sister.
BattleshipA large warship boasting the most powerful guns and the thickest armor, these warships can dish it out and take it right back. Their general drawbacks are their poor maneuvrability, slow fire-rate, and slow speed. The secondary and AA capabilities differ from battleship to battleship.
Battle-cruiserBattle-cruisers nearly match the firepower of a battleship while being faster and more maneuverable at the cost of substantially reduced armor. Again, the AA and secondary capabilities depend on the model of the ship itself.
Heavy CruiserA fast and hard-hitting ship with decent armor, heavy cruisers are perhaps the most balanced ship type. Their AA defense is normally good and their secondary armaments are nothing to laugh at.
Light CruiserWith fast fire rates and weak armor, Light cruisers can certainly be refereed to as 'glass cannons'. They can outrun and out maneuver every other ship besides a destroyer, and their excellent AA can easily destroy entire squadrons of planes.
Flotilla LeaderLarger than a destroyer but smaller than a light cruiser, Flotilla Leader's main purpose is to lead destroyers in engagements. Their thicker armor and larger caliber guns allow them to deal with enemy destroyers with ease, however their large profile increases their detection and chance of being hit.
Destroyer A destroyer's main purpose is to scout the enemy warships and carry out torpedo strikes. They come equipped with large smoke generators than can be activated to conceal themselves and other ships from view. Low firepower is compensated by a high rate of fire and a hard to spot profile.
Destroyer EscortEven smaller than a destroyer, Destroyer Escort's are fast but severely lack in firepower. However, they excel in anti-submarine warfare and scouting enemy forces.
SubmarineSubmarine operate deep under water and use their torpedoes and stealth to damage enemy fleets. They are, however, extremely vulnerable at the surface level with only a small amount of guns for protection.
* Note: These descriptions do not take into consideration the advanced technology of the Fleet of Fog.
Info about specific classes of ships can be found here