PNF is a treatment approach based on the principle that all patients have untapped potential. It integrates principles of motor control and motor learning. The basic procedures of PNF include applying resistance, using irradiation and reinforcement, providing manual contact and verbal cues, and incorporating body positioning, vision, traction, approximation, stretching, timing, and movement patterns. The goal is to facilitate muscle contractions and motor control through optimal resistance applied in different ways like resisting specific motions or muscle groups.