bootloader busybox bios uefi bootloader applet sec pei dxe tsl gran unified bootloader Command-line_interface shells

 https://en.wikipedia.org/wiki/Comparison_of_bootloaders

 https://en.wikipedia.org/wiki/Command-line_interface

 https://en.wikipedia.org/wiki/List_of_command-line_interpreters

 https://en.wikipedia.org/wiki/Comparison_of_command_shells

 bootloader busybox bios uefi bootloader  applet

 sec pei dxe tsl gran unified bootloader

 bootloader busybox  uboot  REDBOOT eCos

https://www.eeweb.com/embedded-linux-design-file-system-and-bootloader/

 Generating U-Boot and U-Boot Device Tree | Documentation | RocketBoards.org

Introduction to Embedded Bootloader Intel SSG/SSD/UEFI. U-Boot Bios-lt Blob(Boot Loader Object Bootldr ARMboot

 available bootloaders relative list  available bootloaders relative list lilo grub loadlin etherboot coreboot blob pmon shboot ubootredboot