What does the fuel reset button, under the glove box, do if pushed?

If there 'ever' comes a time that the engine cranks but won't start... First thing to do is push that button to make sure it hasn't tripped ... Google >inertia switch!!

I was driving my ford f-250 turbo diesel and the gas light had just came on but I only went around 5 miles and it just died and won't start back up even after I put 5 gallons of gas in it and it's getting gas to the fuel filter