Refrigerators were designed as a food storage unit to preserve food and keep it from spoiling. Even the old iceboxes were used to preserve food. You would need to get a block of ice for the box or have one delivered to your home daily. The inside of the box was rather small and therefore, you were limited to the amount of food you could store in this. Normally people stored milk and other items that would spoil overnight if they were not kept cool. Today people store almost everything in a refrigerator to keep it safe so you can eat it again. Storing food that has been cooked will preserve the food so that you can reheat the food and eat it again. There are certain items that will make you sick if they are not kept cold.