Shouldn't the two operating system duties that are considered to be the most important be briefly summarised in this section?

A brief summary of the two most fundamental functions of an operating system should be provided here.

How do the benefits of operating system abstraction present themselves, and which are the most important?

How do the benefits of operating system abstraction present themselves, and which are the most important?

Does the microkernel of the operating system adhere to any particular design principles? How does this method compare to the modular approach, and what is the most significant difference between the two?

Is there not a summary of the two characteristics of the operating system that are deemed to be most important here?

You'll find concise explanations here of the two most crucial elements of operating system architecture.