Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. A Traffic light rating system is a system for simply indicating the status of a variable using the familiar red, amber (yellow) or green of traffic lights.Food sold prepacked may be labeled with a traffic light label showing at a glance the proportions of fat, saturated fats, sugar, and salt using traffic light signals for high ("red"), medium ("yellow") and low ("green") percentages for each of these ingredients. Foods with "green" indicators are healthier and to be prefered over those with "red" ones. The label is on the front of the package and easier to spot and interpret than Guideline Daily Amount (GDA) labeling which will continue. The GDA is difficult to understand for many, including children, and does not lend itself to quick comparisons. The use of traffic light labeling is supported by many physician groups including the British Medical Association and welcomed by consumers.