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I'm reading Operating System Concepts by A. Silberschatz et al. I'm trying to understand what is Dual-mode operation of an operating system.

It states in page 22 that:

Initial control resides in the operating system, where instructions are executed in kernel mode. When control is given to a user application, the mode is set to user mode...

What is meant by control here --- in Layman’s terms? When you say control is given to a user application, does that just mean the user application gets cpu time?

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Control in that context means that the CPU starts running instructions from the user application in the user protection mode after reloading the saved CPU state and switching the VM context.

When control switches, it is more commonly called a context switch. Where the context refers a combination of the CPU state that is saved when control is transferred to another context and to the memory protection and memory mappings that make up a VM context.

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