too long; didn't read linux from scratch
< installing a shell — installing a bootloader — core utilities >
For your BIOS or UEFI to determine which operating system to boot on a given device you may need to install a bootloader.
Back in the day, boot sectors on drives could not contain large files, nor could the execute many images directly. Thus the bootloader was born.
A bootloader is an image which would reside in the bootsector of your drive that could execute images stored in other parts of the drive, and often would support a much larger variety of image types.
With the introduction of UEFI mostly came the primitivization of the bootloader. Bootloaders are no longer necessary to boot into different operating systems.
A user may still be inclined to use a bootloader, but know that with UEFI it is not at all necessary. See the EFISTUB section if you opt not to use a bootloader.
Do note that you will need a bootloader if you have a non-U/EFI system.
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