This statistic is used in the secondary statistics Carry Weight, Melee Damage, and Hit Points. All weapons have a minimum Strength requirement, as well. If your character's Strength is not high enough to use the weapon properly, the chance to hit is modified by -20% for each point of low Strength. A high enough skill can offset the low Strength modifier. You will be warned by a message in combat if your character's ST is too low. Examine the weapon for more details about its ST requirement.