An input device has a first electrode, a second electrode, and a third electrode. The second electrode opposes to the first electrode while being spaced apart therefrom. The third electrode is spaced apart from the first electrode and rotatably or slidably provided relative to the second electrode. By the third electrode being brought into contact with or spaced apart from the second electrode, an electrical state between the first electrode and the second electrode changes. Based on this electrical change, a rotary manipulation or a slide manipulation is detected.