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.
METHOD 1
1. Turn OFF your device to start the whole process. To do that use Power Button.
2. Now press and hold Volume Down + Home button + Power button.
3. After doing this combination Home button should blink and it's over.
4. Your phone restarts and is ready to work.
METHOD 21. Like last time make sure your phone is turned OFF.
2. Next press and hold Volume Up + Power button for about 5 seconds.
3. Then release only Power button, but hold Volume key for 5 seconds.
4. Now before your eyes there should appear Recovery mode screen.
5. Use Volume buttons to scroll, and Power button to confirm.
6. From this menu choose option wipe data / factory reset.
7. And there, well done! Your phone will now restart.