The control surfaces of an aircraft are those parts of the wing or tail that control the direction of movement of the aircraft. These surfaces are ailerons, rudder and elevators. Flaps may be considered control surfaces since they alter the geometry of the wing and change the characteristics of flight but they are not primary controls.
Ailerons are part of the wing, and control the roll of the aircraft around the axis from front to back.
The rudder is part of the vertical part of the tail and controls the turning of the aircraft around the axis from top to bottom.
The elevators are part of the horizontal portion of the tail and controls the up and down movement of the aircraft.
Because of the complex effects of airflow over the wings the rudder and ailerons both are used to turn the aircraft in a controlled manner.