The aim of this course is to examine the electrophysical principles of electrotherapy, the responses of tissues to the electrotherapy modalities widely used in physiotherapy, and to teach the mechanisms of action and application methods of low and medium frequency currents. types, properties of galvanic and faradic current, application methods, physiological effects, electrodiagnostic tests, pain physiology, TENS mechanism, interferential current, diadynamic current, microcurrent, Russian current, ultrareysis current and sample applications. In the theoretical part of the course, the general characteristics, physiological effects and indications of the currents will be covered, and in the practical part, the application types, application prescriptions and application methods specific to different diseases or patients will be learned.