Counters

Each class of ship is best at attacking certain other classes of ship. A class which is highly effective against another class is described as a good counter for it.
For example: Bombers can be countered easily with Fighters. You cannot, on the other hand, counter Bombers with Light Frigates.
 Printable Simplified Counters Chart
https://www.reddit.com/r/SoSE/comments/149qbb/comprehensive_guide_to_damage_types/