I agree with usually, not always. There are plenty of mechanical failures that happen suddenly and without warning.
Have someone turn the ignition to "on" while you listen very closely, and if possible with a stethoscope, to the fuel tank area. You will hear the fuel pump whine if it's functioning.
As was said, check all the fuses, spark, cap and rotor, timing belt, etc. Your ignition coil may have given up, which would be diagnosed if there's no spark coming from the coil wire when you ground it out. If you have spark coming from your coil wire, but no spark from the distributor to the plugs, the problem is likely with the cap and rotor, though usually that will cause degrading engine power and running quality, not just suddenly give up and cause everything to quit. Also check the distributor power wire, which is different than the ignition coil wire. It's attached to the lower part of the distributor and is only a small 18 guage wire. I've had that come off or undone a few times and kill the engine on my old Pathfinder until i soldered it together and onto the distributor permanently.
Good luck!