What is the difference between user and kernel modes in operating system

User Mode and Kernel Mode difference in OS | Operating System

User Mode: 

If you are runing an application program so operating system is serving you in the user mode and the bit is 0. Bit mode values always switch between 0 and 1 it is a kind of signal if the bit mode is 1 that means the Operating system is in user mode. 

Kernel Mode: 

If you make some kind of demand being a user, that demands needs the hardware resources so the OS will switch to the kernel mode because the kernel mode is the only place where using OS's kernel we can access the hardware. 

While switching to the kernel mode operating system switch the bit mode to the 0.

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