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I'm trying to root my Galaxy Note 4 and I see the above terms being used everywhere. What do each of them mean? I have a vague idea about each of them, but I'm still confused about some of them. A brief description about each would be enough. Thanks in advance.

marked as duplicate by eldarerathis Apr 23 '16 at 19:41

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The Term Rooting in android means to gain super user access(Administrator access) for which root access is requires as the su binary should be installed to /system partition.

This is usually done via a Recovery.Every android phone have a in-built recovery which can generally only flash OTA updates and ROM's provided by the device’s manufacturer. So a custom recovery like CWM,TWRP etc is installed.A custom recovery has more features and allows you to flash any suppoerted file.

Each android device has a bootloader which is something like BIOS in PC.And many phones comes with locked bootloader which prevents users from installing any other ROM. Hence unlocking bootloader is a common term related to rooted devices.

ROM stands for Read Only Memory. A custom ROM replaces your device's Android operating system normally stored in read-only memory with a Different OS. Installation of Custom Rom is the process of flashing a Custom ROM usually using a Custom Recovery/ADB


Root - means having "superuser" or administrator access to the OS.

Bootloader unlock - means allowing the device to boot a custom OS.

Custom recovery - allows you to make a complete backup of the internal storage as well as flash ZIPs.

ROM installation - is actual process of installing a custom OS.

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