An Operating System can be seen in two ways
The operating system extends the basic hardware set, adding new functionality that is usable by programs.
The OS hides the specifics and details of the hardware, and instead provides a unified interface to the system.
The operating system fairly allocates resources (memory, execution time, etc) to users and processes. It ensures that the system continues to execute.
In order for applications to be interoperable and run concurrently, there needs to be a common framework for applications to use - That is the Operating System
An operating system is comprised of a kernel and a set of supporting software.
The Kernel is the core part of the operating system.
It is responsible for all of the fundamental operations of the operating system.
For example…
Applications run on the OS
The OS runs on the Kernel