The kernel of Linux is responsible for handling all the interactions between CPU and outside world, deciding the order of all programs share the processor time, effectively managing hundreds or thousands of processes to share the limited memory available in system, skillfully planning the data transmission as a whole to save the time consumed by CPU on waiting for the slower hard drive. Therefore, in-depth study of the most essential parts of the Linux kernel lets you completely understand what makes Linux run normally and why it can work well in various system distributions.