Buy out Price and Exact Price Trading Question

So I just started to use the public tabs, but I'm confused on the two options of "exact price" or "price" If you just do price it puts a "b/o" in front of it, but I always thought that meant exact price anyway? Just not too sure what the difference is.

Buy out is the number that seller estimate it to be. It's negotiable price, so it can go lower or can be offered as other currency if you don't have sufficient amount of the currency that seller asked for. Exact Price or fixed price is a price that is, well, fixed. It is non-negotiable. You either buy it or leave it.

Having a "buyout" price, is SUPPOSED to mean that you could OFFER something else for it, but offering the buyout price guarantees it. "It's worth 2 exalts to me, but I'd be willing to consider a Mjolner"

Setting an exact price means just that, that's all you want for it. You don't know that though because people on Path of Exile don't barter for shit.

Okay thanks!