GRUB - ArchWiki - Arch Linux
wiki.archlinux.org › title › GRUBGRUB. From ArchWiki. GRUB (GRand Unified Bootloader) is a boot loader. The current GRUB is also referred to as GRUB 2. The original GRUB, or GRUB Legacy, corresponds to versions 0.9x. This page exclusively describes GRUB 2. Note: In the entire article esp denotes the mountpoint of the EFI system partition aka ESP.