Why are Device Drivers required?
A device driver is practically required for all plug and play devices, if not for all devices connected to the computer. This includes monitors, printers, CD-ROM readers, optical drives, USD drives, etc.
A device driver is a type of software that allows the device to be recognized by the computer and for the computer to able to communicate with the device. The device driver basically converts the general input/output instructions of the operating system to messages that the device can understand.
Before being able to use any device, one will have to install the drivers of that device onto the computer. If not, the device will probably not work.