Carriers, are, as the water-bound carriers of old, ships that carry smaller, more versatile ships into combat.
Earth's carriers are the largest non-capital ships in the fleet; at a massive 2.5km long, 700m wide, and four decks. They are propelled by PHASE drives (two of them!), powered by a 10-gigawatt reactor, and carry up to 300 small fighters, 25 bombers, 50 dropships and a single command ship.
Deck one is, of course, engineering, AS WELL as non-explosive storage space. decks two and three are nothing but ship carrying space, with no offencive weapons, but two sets of point-defence lasers each. The bridge takes up a large section of these decks, forming a 'nose' on the front. Deck four is the mainframes, crew quarters, and explosives storage (torpedoes, ammo, etc. for the fighters).
As space carriers don't have to contend with gravity, the top of the ship is just armour plating instead of a flight deck, with the smaller ships being launched directly from the hangar floors, and landing in the bay at the bottom of the ship.
The ship has a GIGA-level mainframe, as well as an AI. It has a core crew of 500, but it has a total crew of 905, for all the pilots. It is plated in 7m of Composite armour.