Traffic lights are a really useful thing that you can see on most foods.
It’s the label that tells you how much of certain things like sugar and fat is in your food.
Green means that it is low in that thing, Amber means it is medium and red means it is high in that thing.
They use colours so that you can quickly understand how healthy a certain food is when you go out shopping.
The traffic light system was introduced in 2014, before then you had to learn what was high and low for each category and figure out how healthy something was for yourself!