Frozen food is food that has been stored at a very cold temperature to keep it from going bad.
You know how when you put something in the fridge, it stays fresh for a few days or maybe a week? Well, when you freeze something, it can stay fresh for a way longer time.
This is because freezing stops bacteria (tiny creatures that can make you sick) and other things that make food go bad from growing.
When you want to eat frozen food, you can take it out of the freezer and either heat it up or cook it just like any other food.
Some frozen food is already cooked, like frozen pizzas or chicken nuggets. Others, like frozen vegetables or meat, may need to be cooked before they are safe to eat.
So, frozen food is like having an extra fridge in your house that keeps your food from spoiling for a really long time.