Device driver

a device driver is a group of files that enable one or more hardware devices to communicate with the computer’s operating system.

what devices need drivers :

[card reader.controller.modem.motherboard chipset.network card.printer.scanner.sound card.tape drive.usb devices]

what devices may not need drivers :

Today’s operating systems have a lot of generic(一般的) drivers that allow hardware to work 

[CPU.Disc drive.Fan.Hard drive.Heat sink.keyboard.mouse.monitor.power supply.ram.ups]

Wikipedia:

a driver provides a software interface to hardware devices, enabling operating systems and other computer programs to access hardware functions.