Wow, thanks for the enlightenment. I am really behind the times on this issue. I have a question, though, if wood is so plentiful, why is there so much particle board used? Is it to use every little branch and twig?
For a number of reasons.
First, it is cheaper to make than plywood. Another reason is that it is dimensionally stable, as long as it is not exposed to moisture, and thus can be used in some kinds of furniture very cheaply.
OSB (oriented strand board) may be what you are thinking of. which has much of the strength of plywood, but can be produced at 1/3 of the cost. It is used extensively in roofing substrate, and flooring, in mass produced tract housing.