In Terran there are many types of weapons in the game like cannons, beams, launchers (i.e. missiles). There are also deploy-able weapons like bombs and turrets. In addition, there are drones in the game that may engage or many not depending on the drone.
Weapons, like all ship parts have a 'complexity' or tech level, at the user level. The complexity of the weapon adds to the complexity of the ship and also 'suggests' the effectiveness of the part. For example, a complexity rating of 5 is the best possible, and 0 is the most simple. Yes - we do use fractions; the current turret setting is at 0.5.
Cannons also have a fire hold time .. this will play into how many rounds per min the weapon can fire. It is not as simple as a single number ... lets just call it fire rate and approximate a value.
In general weapons consume power, so in addition to having sufficient concentration level to operate the more complex parts, you need sufficient power output on the ship as well.
Weapons also have a defined 'payload' - this is used to determine the damage per hit the weapon will deal. The exact damage per second (DPS) is calculated at run time with some magic numbers. The core cannons I have in at the moment are small = 2, med =4, large = 8.
Weapons that are turrets like cannon and beam have a traverse speed, or tracking speed; this determines how fast they can turn and affects the time to bring the guns on target
Weapons that discharge a projectile - e.g. cannons, also have a muzzle velocity. This is usually in the order of 300 MPS (meters per second) for a tech level 0-1 cannon.
Beam weapons are special in that they impact the target immediately on discharge in fast flight time.
Missile-like weapons usually have a much slower velocity of a few hundred meters per second at the fast end (just a bit faster than a fast ship) however missiles also do area damage and track the target.