Healing was the restoration of health through the process of recovering from an injury or other medical condition by a patient. Self-healing was the same process but directed by the patient. Healing power and recuperative power were abilities which helped one heal. The healing of physical injuries was typically administered by a medical practitioner such as a doctor, healer, or nurse, while mental health issues typically involved a therapist, counselor, psychiatrist, or psychologist.
Self-induced hypnosis was a Vulcan form of self-healing that required great concentration. (TOS: "A Private Little War")
In 2369, Commander William Riker received two deep cuts from Data's cat Spot. Doctor Beverly Crusher healed the cuts with a dermal regenerator. Crusher incorrectly believed Riker was injured while playing parrises squares and told him that one day he'd break his neck and she wouldn't be able to heal that as easily. (TNG: "Timescape")
In 2370, Voval claimed that when Iyaarans such as himself were injured, their metabolic processes slowed down in order to accelerate healing, making them appear dead for a time. (TNG: "Liaisons")