The main purpose of these notes is to provide an Intelligence Dossier on the various species to help first time players make good initial decisions and investments. If you are the kind of person who would prefer to find these things out for yourself, then read no further.

Species are fundamentally different so that what works in one circumstance won't work in another. Even species with similar biologies, such as Humanity and The Combine, have very different emphases in their technological development which lead to divergent strengths and weaknesses.
When starting a new Space Empire, expand your population base with new colonies, the more the better. Try escorting your colony ships with 1 or 2 DDs unless the destination system is already garrisoned. There are two reasons for this; colony ships are expensive (especially at the beginning when RPs are at a premium) and you never know when a less cautious opponent's unescorted colony ship might stumble into your starship. Leave 1 or 2 DDs as a picket in every system you visit (whether you start a colony there or not). This will deter enemy colonists from homesteading in your neck of the woods.
There are only two ways to evict aliens from their colonies. Bombard them to oblivion or hit them with a Space Marine invasion. It takes quite a while to acquire the military hardware for an effective bombardment. Marine invasions can be put together earlier but as your attacks are restricted to planets your species can colonize, this may not be an option.
You'll need to know about the battle system; firstly to help you with ship design and secondly to help with tactical combat decisions. Species strengths and weaknesses are under individual race details, click the images. ( I =Industry, R=Research and Development, D=Defense, S= Shipyards, M=Marine Training Centers, C=Colonist Training Centers.) You'll find ship design hints in the ships section of this site.

Tactical combat is generic, each race has a 'Base Rate of Fire' (BROF), typically between 20 and 85. This number gives the percentage chance that a given weapon will fire in a particular combat round. It can be increased by researching certain Military Improvements (permanent) and by out-guessing your opponent in the battle system (temporary). It can be increased to more than 100%. For example, a value of 120% means one auto shot plus a 20% chance of a bonus shot. There is no upper limit.
When evaluating opponent's weapon systems, don't forget to take into account their ROF. Information Reports will tell you the BROF for known races.
The Combat Advisor is a useful summary of capabilities and you should consult this before making formation decisions. Decide your next round range to maximize your firepower, unless you know for a fact that your opponent is very weak at a particular range. What determines the range for the next round is a combination of the range choices made by the antagonists and the performance (propulsion) ratings of their fleets. Since all ships are considered equally when evaluating the average performance of a fleet, having plenty of fast DDs will make a big difference in ensuring the next round range is to your liking. Fast DDs will also aid evasion from nasty battle situations.

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