I went to 2 HDs that are about the same distance from my home and they dont' seem to carry it. I asked the people that worked there and nobody seems to know what I am talking about. They asked me, "what is it used for?" Quite frankly, I didn't have an answer.

Can somebody clarify by answering these questions. It would perhaps help others too.
What is the do-able board initially intended for?
Is it a board?
Which section is it normally found in? Lumber, where the panels are?
Thanks for the help!