In order to provide a system in which a single driver can totally control each periphery, there is provided a peripheral determination program executable on a main device installing the driver thereon. The peripheral determination program has a set of instructions including: acquiring device information assigned to each of a plurality of peripheral devices connected to the computer, the driver controlling operations of the plurality of peripheral devices, the device information indicating a model of each of the plurality of peripheral devices; extracting peripheral devices applicable to the driver out of the plurality of peripheral devices, the applicable peripheral devices being capable of executing all settings designated by the driver; selecting one peripheral device from the applicable peripheral devices; and determining the selected applicable peripheral device to be a terminal peripheral device.