Short answers, pulled from the story.
Economists define inflation as an increase in the average price of goods and services measured against money itself. When this general level rises, each unit of currency buys fewer items than before.
Alexander the Great conquered the Persian Empire in 330 BC, which triggered one of history's earliest documented inflation periods. Ancient governments often melted down silver coins and mixed them with cheaper metals like copper to create more currency during this time.
Venezuela recorded an annual rate of 833,997% as of October 2018. This figure represents one of the most extreme monetary instabilities caused by political crises in modern history.
New Zealand became the first country to adopt official inflation targeting in 1990. Most developed nations now use this strategy to steer inflation toward a target around 2%.
Inflation redistributes purchasing power from those with fixed nominal incomes toward people with variable earnings. Pensioners whose benefits do not adjust to prices lose ground while debtors benefit because the real value of their loans decreases as prices rise unexpectedly.