What is GRUB in Linux? What is it Used for?

GRUB is used in different operating systems to allow users to select the operating system among different options. The GRUB program loads the Linux Kernel, and then Kernel does the further processing, like loading the Shell and UI of that OS. GRUB is usually perceived as the boot loader, which is the key part of the overall boot process of an OS. In our today’s guide, we will explore GRUB and will present you with the following learning outcomes:

Let’s start the guide!

What is GRUB in Linux?

GRUB is the abbreviation of the GRand Unified Bootloader, and with the word “Bootloader,” it is clear that GRUB is associated with the bootloader. Yes, when the machine is started, and there are multiple operating systems installed on the machine or multiple options are available to use the single operating system, then this GRUB appears on the screen.

The files associated with the GRUB in Linux are available in the “/etc/default/grub.d” directory, which manages the Kernels and the bootloader of the Linux.

What is GRUB Used For?

As discussed above, GRUB manages the basic configuration of Kernels and Bootloaders in Linux. It allows users to use the operating system among multiple installed operating systems on the computer. It also allows users to choose the way to boot the operating system. For example, the GRUB menu of Linux Mint 21 has been displayed:

In the above figure, it can be seen that there are two different methods of starting Linux Mint 21. One is the default method, and the other one is the compatibility mode. It also offers two other options. One is to test memory, and the other is for the manufacturers to install OEM.

In the same way, GRUB works in all Linux distributions, and with this, we are about to conclude this blog.


GRUB is the abbreviation of GRand Unified Bootloader and is used in Linux to boot the specific Linux distribution or its specific mode. GRUB is the key player in the Boot process as it transfers the control to Kernel, and the rest of the Job is performed by the Kernel. In this particular Linux post, we have demonstrated the purpose and usage of the GRUB in Linux-based distributions.