A hard reset, also known as a factory reset or master reset, is the restoration of a device to the state it was in when it left the factory.
All settings, applications and data added by the user are removed.
The term is often heard in reference to smartphones and tablets but laptop and desktop computers, as well as most other electronic devices, can usually be restored to factory conditions.
1. For a start please turn OFF your device by holding Power button down.
2. Now proceed and prees power button and volume down key and home button at the same time.
3. As soon you see LG logo, let go of the buttons.
4. Now you should be in recovery mode, it looks like this:
5. Scroll down the highlighted area with Volume buttons, and press power button to confirm.
6. Now all you have to do is to choose wipe data/factory reset option.
7. And this is the end of the process, congratulations.