Hyperinflation is a form of economic inflation in which the general price level is increasing rapidly. No single definition is universally accepted; one simplistic definition is a monthly inflation rate of 50%.
Hyperinflation is just out-of-control inflation at an extremely high and unpredictable rate. Rates of inflation of several hundred percent per month are often seen. Extreme examples include Germany in the early 1920s when the rate of inflation hit 3.25 million percent per month, Greece in the mid-1940s with 8.55 billion percent per month, and Hungary during the same approximate time period at 4.19 quintillion percent per month.