An electro-optical device includes a plurality of unit circuits; a first selecting circuit that sequentially selects the plurality of unit circuits; and a first signal line through which correction data for the individual unit circuits are supplied serially. The method includes scanning data for viruses before it is sent from the computer and attaching a certificate identifying the data as being scanned for viruses if no viruses are found during scanning. A participating consumer with one card, can instantly purchase pharmaceuticals and charge the transaction to a credit card and earn and apply savings dollars redeemable for pharmaceutical purchases.