being able to control the exchange would mean monopoly, which is not a good thing. But it's basically how companies trade, only companies can trade non-currency on it, not people, the exchange covers currency, public shares, and general resources like grain, the ask is what a seller wants for a single unit of the good in question, while the bid is what a buyer is willing to pay, as such the Highest bid and highest ask never overlap, as that would quickly be resolved by the systems of the exchange.
if you want to participate In the exchange then you need to make a company, go to the items part after someone works at the company and press the sell on the exchange, then the price will be set at the last price where goods were exchanged at, and then you need to input the amount you want to sell, and press the blue button at the bottom, if someone is willing to pay more than you set for what you want for such goods, then it will automatically sell the goods sent to the exchange.
