Numismatics is the study or collection of currency, including coins, paper money, tokens, and related objects. People who practice numismatics are called numismatists. This field covers not only the identification and cataloging of coins and money but also their history, production, and cultural significance.
Numismatics can involve:
Collecting coins from different countries or historical periods
Studying the design, materials, and minting techniques of coins and notes
Researching the economic and social history reflected in currency
It’s a popular hobby for many, but also an important academic discipline for historians and archaeologists.