Tools

Weapons
"Gimme a ship and weapons", a wise man once said. All ships only have one weapon slot for each kind of weapon (turret/laser/missile). It is not possible to install more modules of the same weapon type (i.e. installing two turrets).

All weapons use energy. Once the energy pool is empty, the weapon can't be fired any more. So it's mandatory to keep an eye on the energy consumption of the weapons and not simply look for the damage values alone. There are modules as well as boosters to aid the ship in maintaining enough energy.

Weapons come in different tiers, whereas legendary gear is the best. There are two reliable ways to obtain legendary weapons: The only other way by now is by completing a quest involving Hal_Jaenke. However this is a one-time option only, whereas the other options can be done repeatedly. (How about salvaging? - Tooltip?)
 * Kill a wormhole boss
 * Kill 36 or more enemies during a space battle in a faction war

Turrets are best used in close combat. The farther away the target is, the more bullets will miss, reducing the damage done. Lasers hit instantly, therefore they can be used quite good up to midrange. They need some time to reload, but are able to destroy weaker ships with a single blow or finish off already weakened ones. Missiles are a bit different. First the target needs to be locked on, but after doing so the missile will follow its target on its own. Meaning, unlike turrets or lasers there is no need for a visual contact after a target has been locked on.
 * Turrets
 * Lasers
 * Missiles
 * MISC TOOLS

Modules
Modules can amplify many aspects of the ship. They can strengthen the shields, make them regenerate faster, increase the damage of the weapons, give more cargo to store loot and so on... There are several categories for modules and each category has its own set of modules.
 * Defensive
 * Offensive
 * Modification
 * Drones