Before the industrial era (1800s), the line between currency and commodity was much blurrier than it is today. Since money performs many functions such as being a means of exchange, a unit of account and a store of value, it makes sense that people used different types of monies for different things in the past. For many centuries, people used beads, pelts and shells as a means of exchange. Double entry accounting systems enabled people to manage debit and credit systems using their own units of account. Gold and silver have been used as a store of value, often in the form of jewelry, religious objects and architectural ornaments, for thousands of years. Other commodities that have performed monetary functions in the past include slaves, livestock, grain, liquor, copper, salt and many others. While governments have always been able to create their own currency and pressure people to use it, before the industrial era’s unprecedented centralization of production, communication and bureaucracy, governments couldn’t effectively prevent people from using other monies to transact.