What is the difference between physical and occupational therapy?

Specialization. In general terms, occupational therapy is a specialized form of physical therapy. Pts may focus on treating an injury and healing the body. Ots focus on assisting the patient with daily activities/occupations. It can be activities like self care (eating, cleaning, dressing, cooking), mobility (opening doors, using equipment), or work (keyboard, work station, operating work tools).
Subtle difference. Physical therapy focuses on restoring function to the body through exercises, such as stretching and strengthening and correcting poor biomechanics. Occupational therapy focuses on restoring the ability for one to function on performing certain activities.