When the pandaren were subjugated by the mogu centuries ago, it was the monks that brought hope to a seemingly dim future. Restricted from using weapons by their slave masters, these pandaren instead focused on harnessing their chi and learning weaponless combat. When the opportunity for revolution struck, they were well-trained to throw off the yoke of oppression.
Whatever their combat role, monks rely mainly on their hands and feet to do the talking, and on strong connection with their inner chi to power their abilities. Abilities such as Expel Harm and Chi Wave both heal their allies while at the same time damaging their enemies.