Positive energy

Positive energy was the energy empowering living beings with life. It originated on the Positive Energy Plane and manifested as a white, glowing surge of power. Positive energy healed living beings. It was the opposite of negative energy and caused harm to undead.

Clerics
Clerics were adept at using the power of positive energy. Good clerics wielded positive energy to turn or destroy undead creatures. Positive energy was also the power behind healing spells, such as cure light wounds.

Wizards
Certain arcane spells like Simbul's synostodweomer could convert the energy of a spell into positive energy, which could then be used to heal.