Hit Points

Hit Points (abbreviated "HP") represent two things in the game world: the ability to take physical punishment and keep going, and the ability to turn a serious blow into a graze or near miss. As you become more experienced, you become more adept at parrying strikes, dodging attacks, and rolling with blows, such that you minimize or avoid significant physical trauma, but all this slowly wears you down.
Rather than trying to keep track of the difference between attacks and how much physical injury you take, Hit Points are an abstract measure of your total ability to survive Damage. As long as you have at least 1 Hit Point, you can act normally on your turn.