An air supplying apparatus may include, but is not limited to, a pump, a motor, a housing, and an intake unit. The reference pH sensor is an extended gate field effect transistor structure and comprises a metal oxide semiconductor field effect transistor on a semiconductor substrate, a sensing unit comprising a substrate, a solid-state conductive sensing layer on the substrate, and a polypyrrole layer on the solid-state conductive sensing layer, and a metal wire connecting the MOSFET and the sensing unit. The conductive adhesive film is positioned between the plurality of front electrodes and the interconnector in the second direction crossing the plurality of front electrodes and electrically connects the plurality of front electrodes to the interconnector. When the user writes with the stylus, or uses it as a pointer, an operative end of the stylus is brought into contact with the interface surface. The file server communicates, to a client, at least a portion of the information for use by the client in determining whether to perform a direct inputoutput operation on the storage medium that would change data stored thereon.