Question

what are device driver why are they needed

Answer 1

A device driver is a program that controls a particular type of device that is attached to your computer. There are device drivers for printers, displays, CD-ROM readers, diskette drives, and so on. When you buy an operating system, many device drivers are built into the product.

We need device drivers to be able to use your devices. Our computer needs drivers to be able to communicate with the devices that are connected to it. Without the right driver, a device is nothing more than a piece of hardware that doesn’t work. Which is probably why device drivers are called drivers.