ADB (or Android Debug Bridge) is a handy command-line tool that comes with Android SDK and lets you communicate with a device, unlocking access to the system folders to perform a variety of versatile device actions.

ADB works only if Developer options have been activated on your Android device and USB debugging mode  has been enabled. Since ADB is mostly applied to tweak hidden device settings, using it requires additional skills and may be probably not for the beginners. It is recommended to use MTP mode instead unless you are experiencing any connection, file transfer or other issues in ADB mode.

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