Historians aren't quite clear about the origins of Valentine's Day.

There are stories about St. Valentine getting letters in prison, and English legends about a day when birds are inclined to pick their mate. Then in the sixteenth century we find the first paper valentines getting sent to sweethearts. And somewhere along the line, the idea of Cupid and his magical love-arrows got recycled from Greek myth.

The tradition doesn't have one starting-point -- it just kept growing, pieced together from different places.

This is a lot like the labels that are used to represent environmental concerns on the products we buy. Certain terms, images and ideas are in the air, then they start showing up on the sides of boxes. But if we want to be environmentally intelligent when we shop, we should really know what it all means.

Like Cupid, the Recycling industry has done it's own recycling of arrows. You might not realize that the triangular three-arrow symbol hasn't been around forever.

The image was designed in a 1970 competition sponsored by Container Corporation of America, who intended to register the symbol for use on containerboard packaging. A University of California graphic design student by the name of Gary Anderson created the winning image, which became the prototype for the common symbol.

Meanwhile, the registration was never completed at the patent office. And with the immediacy and clarity of the arrows, the mark quickly spread into wide public use. Now it's inseparable from our understanding of the terms, Reuse, Reduce, and Recycle.

The problem with public domain is that there are no controls over how the image is used. So as the three arrows became more popular, their message became more vague. They could and have been used to promote almost anything.

This confusion of labels is a common problem when it comes to buying recycled products. Consider the following terms:

• 100% PHOTODEGRADABLE PLASTIC: The word 'degradable,' applied to plastics, is a touchy issue. Plastic, by its very nature, is inert. That means it does not react with other substances, and that it will not break down under most conditions. Degradable plastics contain additives which cause the material to break down into small particles, but not to truly decompose.
• PRE-CONSUMER RECYCLED: When you see this on a label, it means that waste made during the manufacturing process, often of paper and plastics, has been used in the product in front of you. While this is certainly prudent business, it's a standard practice of any efficient manufacturing operation.
• POST-CONSUMER RECYCLED: This is the one you should be looking for if you're shopping green. The term means that whatever percentage given is made from manufactured, bought, used, and returned materials.

Keep your eyes open for those 100% post-consumer valentines.