and batteries, candles, matches, etc...
If you loose power and don't have any heat, DON'T USE your gas oven or top burners to heat your house.
A gas range produces carbon monoxide gas which is odorless and can kill you and your family.
It is just like attaching a hose to the tail pipe of your car and running it though a window to the inside of your house.
Think before using any alternate heat if the power goes out.