Hard Reset (Cellular phone)
Hard resets clear the saved settings in the cell phone and restores it to the factory defaults. A hard reset should be done only as a last resort (see the cell phone owner's manual for more information).
Soft Reset (Cellular phone)
This helps to restore the basic functions of the phone. To do a soft reset, turn the phone power off, remove and reinsert the cell phone battery, then turn the phone back on.