Grub Customizer is a software package that does exactly as the name would imply. It allows the user to customize different aspects of the grub boot menu – such as the order that entries appear in the list, how long grub waits before selecting a default system to boot to, etc.
The purpose of this tutorial is to show how to set kernel boot parameters in Linux. When a user boots their Linux system, the GRUB boot loader can set various parameters as it loads the Linux kernel. You can think of these parameters as arguments, the same type you are probably accustomed to using with commands in your terminal.
GRUB is the acronym for GNU GRand Unified Bootloader: it is the bootloader used in practically all Linux distributions out there. Early in the boot stage, the bootloader is loaded by the machine firmware, either BIOS or UEFI (GRUB supports both of them), and it loads one of the available kernels. Being an essential software, grub is installed by default and available in the official repositories of distribution we are using;