The on-board computer got a bad signal from one of the few hundred sensors on the driveline and pulled all your horsepowerz away until you get it fixed.

It may reset itself but most likely it will come back.

And from your apparent lack of automotive knowledge (based solely on your very basic question). Have your car scanned at a reputable shop and they should be able to tell you what is in error and you can decide how best to handle it.