Improperly storing food is a guaranteed way to cause food borne illness. Make sure you store your food properly to prevent bacteria from growing on food. By following these simple tips you can keep your food and family safe:

• Always put perishable items away as soon as you get home. Never keep items, including leftovers, out for more than two hours. If it's a particularly hot day limit the amount of time an item spends outside the fridge or freezer to one hour.
• Make sure you read the labels on items before putting them away. Some items can be stored in the pantry before being opened but need to be refrigerated after opening, like sauces and condiments.
• Ready-to-eat foods should be used as soon as possible including lunch meats. The longer they stay in the fridge, the greater the chances of bacteria growing.
• Keep an eye out for moldy food. Mold can grow even in the fridge. If you see anything that looks moldy, throw it out. Try to keep your fridge as clean as possible, and throw out food that has gone bad. 

Are You Storing Your Food Safely? [U.S. Food and Drug Administration]