and here I was thinking of something simple like the math involved in a D&D game, where a simple role of the dice would let you know how much damage you have inflicted. I had always imagined that's how Video Game RPGs kind of worked. Your weapon would have a top set of HP it takes off while your STR would act as your bonus buff points and a number is chosen at random to decide how effective the final hit would be.

like if a weapon has 20HP it takes off tops.
and your STR is +40 (in this case let's say the amount this adds to the weapon is half of the +40 so it would be 20HP)
then a number is chosen at random between one and twenty at how efficient that attack would be.
Lowest/weakest attack would be 20HP taken off, while strongest attack would be 40HP taken off.
(20 + (40) 20) w/ (R) = Attack

and then on top of that you can add armour and equipment buffs or de-buffs.

or am I totally wrong in this way of thinking?