There are three general categories of physical therapy treatment: exercise and functional training, modalities, and manual therapy.
Therapeutic exercise and functional training include exercises and activities that are designed to strengthen weak muscles, correct muscle imbalances, improve flexibility, and/or re-route neural pathways to change patterns of movement.
Modalities are non-invasive treatments applied to the patient that have the general goal of reducing pain and inflammation and promoting healing by increasing blood flow. Modalities include hot packs, cold or ice packs, ultrasound treatments, and a variety procedures involving electrical current (electrical stimulation). There are others but these are the most common.
Manual therapy is a general term referring to various types of hands-on treatments delivered by the physical therapist. This can include massage, stretching, joint mobilization, or manual traction.