Health - The health stat represents your characters overall physical condition. Your health decreases as you take damage in combat, and replenishes with time, medical aid, or rest.
Stamina - Stamina is what allows your character to perform actions during combat. Attacking, blocking, and sprinting all require stamina. Stamina recharges quickly when it's not being used.
Shock - Shock represents how much damage your character can absorb in a short period of time before falling unconcious. Unlike the other stats, your shock rating starts at 0% and rises toward 100% as you continue to take damage. The shock bar will reset completely if you take no new shock damage for a period of 16 seconds. However, this timer will reset each time you take additional shock damage. It is possible to be knocked unconcious due to shock, even if your health is no where near depleted.
Primary Attack - Primary attacks are attacks made with your primary weapon, and are your most obvious means of damaging your opponent and winning a fight. To attack with a weapon costs a certain amount of stamina; the heavier the weapon, the higher the stamina cost to attack. Attacks will inflict a certain amount of damage based upon the weapon and the characters stats and skills. Attacks occur in real time, with one press of the button equaling one attack. Attacking will be a complete waste of stamina if you miss; accuracy is entirely up to the player.
Secondary Attack - Secondary attacks are attacks made with an object in the secondary hand. They can be shield bashes, back hand strikes, slashes, throwing objects, or whatever. It all depends on what's equipped in the secondary hand. Secondary attacks usually have entirely separate stamina costs, damage, and special effects from primary attacks.
Block - Blocking is how you defend yourself against your opponents attacks when you have a shield. Your opponent will not know when you are blocking until they attack. If you are blocking when they attack, their attack will be deflected. Simply holding down the block button does not cost stamina, but it freezes your stamina recharge until you release the block. Blocking only costs stamina when you successfully block an attack.
Dodge - Dodging is your fallback defense if you do not have a shield. It costs significantly more stamina to dodge than it does to block. However, holding down the dodge button will not freeze your stamina. Because of the high stamina cost, it is easier to be overwhelmed by a fast burst of attacks if you do not have a shield.
Sprint - Holding down the 'Run' button will cause your character to sprint during combat. Sprinting costs stamina, but allows you to traverse ground more quickly. This can be used to get into or out of danger quickly, or to maneuver against your opponents in battle.