What is Windows Boot manager?

Question

Windows

After installing windows (7 or 10), this system is loaded only through a certain Windows
Boot manager, explain what it is? in the boot priority, first there is the inscription Windows boot manager and then the hard disk model, when you try to boot from the hard drive without the windows boot manager mark, just a black window with some inscriptions pops out, and nothing happens, what is the windows boot manager and why is it needed Why is the OS only loaded through it?

Answer 1

Because, each operating system is loaded through a bootloader - a special code that initializes the hardware, and then transfers control to the kernel.
For Linux, this is most often Grub or, in more modern distributions, systemd-boot. In modern Windows, it is called Windows Boot Manager.
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