What is bootloader,why bootloader already locked, how we unlock bootloader , why bootloader unlocking needed

The main part after rooting the android device is to unlock bootloader through PC and its will erase your all data and only system will remain...

 

The newly released approximately every mobile have there boot loader locked because of the bootloader of your mobile of you mobile due to this you cannot flash you ROM into mobile.. (which adb fastboot require in you pc)

If you are going to unlock boot loader the first boot elapse so many to open your device but don't be panic,, its work,, work and it will gives you so many happiness because its very loving if you doing it for first time,,

You can unlock boot loader before rooting your phone also,,,,

After unlock boot loader you can flash any ROM which you have to flash like new kernals and many tweaks like xposed installer and newest android 'o' ROM , cynogen mod 15.0 and many more
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,, after all you can customize you mobile as you wantsafety

IMPORTANT

this is only for your knowledge and teaching purpose so dont do anything without knowing everything...

or you can meet the experienced person...