How do drivers become a part of the kernel?

Question

Someone told me that for most operating systems, the drivers become a part of the kernel. How does this happen? Does the kernel decompile itself, add the driver, and recompile itself? Or are the drivers plug ins for the kernel? Are drivers even their own separate programs?

Answer 1

A driver is compiled into a library that exposes a known interface. The kernel then scans for drivers on startup and loads them into kernel memory. Some operating systems, such as linux, also support kernel modules that can be loaded / unloaded while the OS is running...