Little known fact: cats are fantastic engineers. Go ahead and ask about it next time you see one. In case you don't speak feline, "meow" means "that cantilever is deflected over its g-type joist girder." It's probably going to say that a lot.
The people in the Red table are looking to buy this item for the price listed.
The people in the Blue table have the item and are willing to sell it for the price listed
The top of the table is the best price (highest bid / lowest ask)
Items listed are assumed to be unremarkable, no name tags / paint / fancy lvls / low craft numbers / etc
Click on a price in the bid/ask column to sell/buy the item and follow the instructions