what is meant by kernel and how it defers from operating system..??

Answer 1

An operating system is a computer program that manages the hardware and software resources of a computer.

The kernel is the central component of most computer operating systems.
The difference is that Kernel is central to the OS, but there are also other components which help the kernel. ( Like observing the user input )

Answer 2

Oh man it's been awhile since i took O.S. in college... But basically, the Kernel is the central part of the operating system. It handles the lowest of all the instructions, and one thing i know for sure is: if your kernel breaks, your computer dies.