Newbie Guide:
Upper and lower body armor are classified as either robes, light gear or heavy gear. Robes are for Mystics and that ilk, so we'll skip them and move directly to light and heavy gear.
When you refine your profession at Level 20, the armor you wear will influence your choice of skills. For example, Heavy Armor Mastery is a skill which increases defense only when heavy gear is worn. Likewise, Light Armor Mastery improves evasion only when wearing light gear.
Keep in mind, you are only considered to be equipped with a given type of armor if both the upper and lower body are protected by the same armor type. Heavy Armor Mastery, for example, will not activate if you are equipped with, say, a Bronze Breastplate and Leather Pants.
These skills are only affected by your upper and lower body armor. Your helmet, gloves and other gear don't affect either skill, so wear whatever you want.
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