Related to the answer of the following question:
How are evolution and variants of aircraft considered by certification authorities?
Are the terms "Aircraft Version" and "Aircraft Variant" synonyms? ...
Based on this question, I learned that the F and A-Letters in the naming of (military) aircraft reflects what their intended purpose is.
A: Attack (Air-to-ground)
F: Fighter (Air-to-air)
their names ...
In my understanding, "F" stands for "fighter" (air-to-air) and "A" for "attack" (air-to-ground). E.g.,
the F/A-18 Hornet can attack air and ground targets, which is why it's called F/A-18.
the A-10 ...