What does a computer exactly do when we shut down?

Why is it neccessary to shut down a computer? What process happen inside when we shut down a computer?

What does a computer exactly do when we shut down?

hi, when we shut down the CPU closes all the programmes and RAM save unsaved files.The CPU loggs off the user and even processes the updates.It is neccassary to shut down as the maxim says "access of everything is bad",the computer also get exhausted.
saving ur settings

logging past its sell-by date

then shut down
it save the settings youv made and changed...improper shut down can result in data loss....

if a virus be detected...do not shut down your computer...because it stays at the memory...once its saved and shut down..the virus will run to your hard disk...the best point to do in a crust like explicitly to do an improper shut down....in that get it??=)
Like the refrigarator the restrained goes sour.
It is important to close any overt files, otherwise lost clusters on the hard disk could result. Windows also save your current configuration of the desktop and settings, so that it can restore them on reboot. That's basically it.
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