Bootloader is the heart of Android rooting because the bootloader allows you to install custom ROMs in your Android device.
What is a Bootloader?
A bootloader is a program that loads the operating system when you turn on your device. It runs before Android starts and initializes the hardware before handing control to the OS.
Locked vs Unlocked Bootloader
Most Android devices come with a locked bootloader, which prevents you from installing custom firmware. To install custom ROMs or gain root access, you typically need to unlock the bootloader first.
Important Warning
Unlocking the bootloader will void your phone's warranty, whether using official or unofficial firmware. Once unlocked, the phone manufacturer will not be able to take any guarantee of your device to work properly.
How to Unlock
Bootloader unlocking procedures vary by manufacturer. Each Android smartphone brand has different methods for unlocking the bootloader.