Hand to hand combat means any combat utilizing fist and feet, or brawling weapons (club, cudgel, etc). Hand to hand combat includes any of a variety of martial arts (unarmed combat) or brawling.
Additional/Reduced damage due to strength
Hand to hand damage is modified based on the characters current strength, using the following table:
The character has been trained in a martial art. Treat hands and feet as daggers, elbows and knees as blade. If the character is evading, they add their level of unarmed combat to the DM.
The character has experience street fighting. Characters will brawling do +1 damage for each level of brawling skill. Also, damage from an opponents attack is reduced by 1 for each level of brawling, due to the characters ability to 'roll with the punches'.