A computer software utility or program that operates a specific attached peripheral device or interface. The peripheral device, such as a printer, requires certain commands and signals in order for it to function; the driver (also called a device driver), typically supplied on a floppy disk or other media with the device, serves as an interface between the main computer or application (such as a word processing program) and the device itself, interpreting and processing the data from the application to the appropriate form for the proper operation of the device. Some computer operating systems include drivers for commonly-used peripheral devices, such as laser printers.