Some basic concepts

Kernel: http://en.wikipedia.org/wiki/Linux_kernel
User space: http://en.wikipedia.org/wiki/User_space
Input/Output (I/O): http://en.wikipedia.org/wiki/Input/output
Udev: http://en.wikipedia.org/wiki/Udev
Devicekit: http://en.wikipedia.org/wiki/DeviceKit

more to follow