Trading resources, selling resources you produce too much of and buying those you need is a great way to speed up the growth of your empire, and can help you to become quite powerful with practise. You may choose the amount of a resource you want to sell or buy on the market, and at what price, and the market will do the rest. If you cannot buy or sell the amount desired in one go, it will be done automatically as other sellers or buyers come to the market with the goods you want, and you will be kept updated through the news page.