Another important aspect of the game is relations with other players.
Politics is a weird concept. It takes into account respect of you for others, and theirs for you, the weight your words carry is often influenced by this, and thus your actions often determine how other players interact with you on every level.
Countries need many products and their corporations buy raw materials and sell their produce. Most of the buying and selling takes place on the world market. Trading is massive with many thousands of transactions taking place in real time 24 hours a day in all worlds. The world market is a true market with price fluctuations depending on demand and supply.
Many of the corporations are public and their shares are traded on the stock market. All players have access to the stock market and use it to invest some of their reserves and to try and gain control of corporations they are interested in.