<human>:  Explain what the concept of inflation means.
<bot>: Inflation is the sustained increase in the general level of prices and fall in the purchasing power of money. It is an economic term that refers to a rise in the cost of goods and services over a certain period of time. Inflation occurs when prices are rising, or when currency is losing buying power. Inflation affects different areas of the economy, such as wages, interest rates, and investments. Inflation is measured in percentage terms and is typically determined by the Consumer Price Index (CPI).