Hyperinflation is an extremely rapid increase in prices. Hyperinflation typically occurs when the central government greatly expands the money supply or when there is a loss of confidence in the currency. This situation usually arises when a country undergoes an unusually stressful budgetary situation, such as a budget shortfall caused by a collapse in commodity prices. The government then chooses to print far too much money to overcome its financial shortfall, so that the supply of money greatly exceeds the demand for it.
When hyperinflation persists, the currency effectively becomes unusable, so that consumers must instead engage in barter transactions or the use of a foreign currency. Consumers are also more likely to avoid currency holdings, instead investing in hard assets. Doing so drives up the price of hard assets, since everyone is engaged in the same behavior.
Hyperinflation can be resolved by halting the printing of more money, combined with a conversion to a replacement currency. These actions require the support of a government with a proper knowledge of economics. Since the government started the hyperinflation, it typically requires the replacement of that government with a new one in order to halt the hyperinflation.