Missiles are long range but slow to fire.
Beams are mid range but have a moderate fire speed.
Kinetics are short range but rapid fire.
Ships have a dodge chance. Attacks that are dodged deal no damage. Fighters/Bombers (tiny hulls) get a +50% to dodge. Its like they come with built in defenses. Frigates (small hulls) get a +50% to hit so they are fighter/bomber killers.
Shields block damage. They are like hull points but they refresh after every battle. They take damage before armor.
Armor blocks damage. Roll a number from 0 to armor rating. That is how much damage will be blocked by the armor for the given attack. The remaining damage deals hull damage. Armor is not reduced by damage.
Hull. This the ships hit points. When it drops to 0 or less, the ship is dead.
In general, you use fighters/bombers to harass and destroy large ships. I recommend giving them kinetic weapons as they fly very fast in battle and can quickly get into weapons range of their targets. Frigates are for killing fighters and bombers. Medium ships get much more equipment space and hull points.