I know MBR bootloaders, the MBR bootloader must switch a computer to the protected mode (as rule) and pass the control to OS kernel, for example here. But what's UEFI bootloader? As I've read UEFI is a some microsystem (like BIOS but it does more stuffs). But what does bootloader do in UEFI case?
I tried to read about it on OSDev Wiki but I got almost nothing, unfortunately... Maybe due to my poor English.
Can someone explain me general steps of a trivial UEFI bootloader to load OS kernel and pass control to it? I couldn't find samples.
P.S. Of course, all operating systems are different same as computer architectures but I mean x86_64 architecture with 64-bit or 32-bit OS kernel.