Nandroid Backup
Download TWRP Backup and Restore Tool for PC (Unofficial)
Do you flash custom ROMs often? If you do, or even if you have flashed something just once, there’s virtually no way you have not
Fix PIN Errors After Restoring Nandroid Backup in TWRP
Once your device is rooted and you begin tinkering with mods and custom ROMs, a nandroid backup will start coming very handy. Who knows