A health professional, healthcare professional, or healthcare worker is a provider of health care treatment and advice based on formal training and experience. The field includes those who work as a nurse, physician, physician assistant, registered dietitian, veterinarian, veterinary technician, optometrist, pharmacist, pharmacy technician, medical assistant, physical therapist, occupational therapist, dentist, midwife, psychologist, audiologist, or healthcare scientist, or who perform services in allied health professions. Experts in public health and community health are also health professionals.