Common grocery store labels and what they really mean

Aside from the fruits and vegetables at the periphery of the grocery store, it can be very difficult to know what (if anything) might actually be healthy. Since most food product manufacturers take liberty with splashing all sorts of quasi-health claims on their products, it is worth knowing what labels mean and who is in charge of granting a label. For example, did you know that "zero calorie" actually means up to 5 calories (or that "zero calorie" soda might not actually be healthy at all) What about "certified organic"? What does that mean and Who is doing the certifying? Thorin from Lifehacker has a great post on a lot of these labels that is certainly worth a read. Also, one of the first commenters made a point that I am always quick to make: if it comes in a box, you probably should not be eating it. I would add, if you are not cooking it yourself (warming and microwaving does not count), it is not real food.