The beauty of a paper bag used to be its simplicity, but today they’re covered in a collage of symbols and advice. When it comes to an average bag has at least six key pieces of information on it. But what on earth do they all mean? The most obvious symbol is of course the massive green logo, which blends together a large W with fresh pieces of produce.

But underneath it there’s a claim that 85 percent of the bag is made from recycled paper. Surprisingly all recycled paper isn’t equal. For instance the claim can apply to paper made from fallen wood chips and sawdust when logs are sawn, adding value to trees felled by logging companies.

But when it comes to Woolworths bags the company has assured Yahoo, only post-consumer recycled paper is used. Woolworths bags made in Australia display that claim boldly on the side of the bag, but with those made overseas, you’ll find that information displayed underneath. Those made in Australia can be marked with four little letters you may not be familiar with — PEFC.

While those made overseas carry the FSC logo. Both are certification schemes meant to ensure the trees have been sourced sustainably, but conservationists argue there are key differences between the two. FSC is the mark of the international Forest Stewardship Council and it ensures paper with its mark does not harm populations of endangered species like koalas.

PEFC stands for Programme for the Endorsement of Forest Certification, a program that certifies high quali.