The fleet strategies you set based on the type of weapons the fleet tends to carry, or the role you want it to perform:
Optimal Firing Range is good for fleets that have weapons whose damage decrease over range, or for fleets going up against enemies that are hard to hit; it will bring your ships into the best range to do lots of damage and hit the most often.
Maximum Weapons Range is good for fleets with lots of long range weapons with bonuses to hit, such as missiles or Wave Motion Guns. With Maximum Weapons Range, the fleet will try to stay as far away as it can from the target while still being able to hit the enemy. However, there is a bug in this strategy which causes ships with this strategy to charge in blindly on turns when the ship's weapons are reloading; the Ultimate Strategies Mod's "Max Range Slow Reload" strategy fixes this bug.
Capture Enemy Ships tells the fleet to attempt to board and capture enemy ships; it is only useful if at least one of the ships in the fleet has Boarding Parties (research Military Science level 2 then Ship Capture). When all the boarding ships have used up their boarding parties, the fleet will attempt to fire at optimal range.
Capture Planet will tell your ships to attempt to capture a planet; it only works if at least one of your ships is carrying troops (research Construction level 1 then Troops). If all transports are depleted, the fleet will attempt to fire at optimal range.
Don't Get Hurt is good for unarmed ships; it will send them to cower in the corner of the screen and stay out of the main combat; sometimes they'll actually run out of the corner if someone dares to approach
Ram is useful if you install warheads on your ship (or lots of armor, especially armor which can regenerate!), or the ship has no chance of surviving combat anyway. (Ramming with colony ships is a valid and not uncommon tactic!
) Be aware, though, that the ramming ship takes 2/3 more damage than the ship being rammed, assuming both ships have the same number of hitpoints - and the ramming ship doesn't get to use its shields while the target does!
Fighter Attack and Drone Attack are special orders that should not generally be used for units other than fighters and drones; I think Fighter Attack makes your fighters fly in really close and fire away, while Drone Attack makes the drones ram, weapons blazing.
Point Blank and Short Weapons Range force the ship to fire up close; there's really no point that I can see to using them in place of Optimal Weapons Range.
Is that everything?
You can also customize your own strategies in the Empire Options | Strategies window, or, to make them persistent from game to game, edit the entries in DefaultStrategies.txt (you might want to make a backup of the original first!) or download the Ultimate Strategies Mod from
www.spaceempires.net