After many hours of battles and experience, you will eventually gain the ability to see your hitroll and damroll. Your hitroll is the bonus given above and beyond the random number generated by the Mud. This involves your chances of hitting your enemy. Without a high hitroll, you are doomed to miss often. Many pieces of magical equipment around provide you with special hitroll bonuses; identify everything!
In Game Use
HR is the one a few of the stats that determine how much damage an archer does, the others being the min-avg-max damage of their bow and their race's archery modifier. DR does nothing for missile weapon damage.
HR doesn't modify the amount of damage done by ordinary (non-missile) attacks, but it does raise the probability of attacks successfully hitting an opponent. Most hero warriors feel that their HR is "good enough" in full hitter gear, and instead choose to focus on raising their DR as much as possible. This strategy may not work as well if you're utilizing weapons that double hit. More attacks means more chances to miss, which means that you have more of a use for a higher HR bonus.