Q. Device drivers in Windows system?
In Windows system device drivers are implemented as dynamic link libraries (DLLs). This scheme has advantages which DLLs comprises shareable code that means only one copy of code needs to be loaded into memory. Secondly a driver for a new device can be implemented by a software or hardware vendor without need to affect or modify Windows code and lastly a range of optional drivers can be made available and configured for particular devices.
In Windows system the concept of Plug and Play device installation is needed to add a new device like a CD drive etc. Objective is to make this process largely automatic. The device would be connected and driver software loaded. Subsequently the installation would be automatic. The settings would be chosen to suit host computer configuration.