I looked through the index threads, but I wasn't able to locate a source for this information.
When using space player abilities, certain visual and audio indicators pop. It's helpful to know what these indicators mean, especially when playing in groups.
For example, if I proc a Jam Targeting Sensors on an ememy ship, it's surrounded by a blue cloud. If I engage High Yield Torpedoes, an old-school torpedo sound is followed by a glowing red indicator on my ship. Emergency Power to Shields makes a "shield bubble" around my ship.
I noticed I can try to hover over little buff/debuff icons on my target to try to see what is happening, but that can be tough in combat.
It appears a solid square also indicates that a system is down, but I am not sure which one, unless their shields all suddenly disappear. (Torpedoes, full spread!)
Maybe I will just learn them all over time, but is there a listing of these indicators? I've found it handy to know when I should pop up my shields, launch torpedoes, etc.