A person who enjoys collecting coins and studying different types of money and currency clearly has an interest in numismatics.
Numismatics refers to the study and collection of currency, including coins, paper money, and medals. People who study numismatics are called numismatists. They learn about the history, art, and even the materials used to make money throughout different time periods. To a numismatist, every coin, dollar, and token tells a unique story about the culture, economy, and technology of its time.