Ethereum tokens can represent anything from a physical object like gold (Digix) to a native currency used to pay transaction fees (Golem). In the future, tokens may even be used to represent financial instruments like stocks and bonds. The properties and functions of each token are entirely subject to its intended use. Tokens can have a fixed supply, constant inflation rate, or even a supply determined by a sophisticated monetary policy. Tokens can be used for a variety of purposes such as paying to access a network or for decentralized governance over an organization.