Numismatics is the study of coins, paper currency, and medals. It comes from the Greek “nomisma,” meaning “current coin.” The noun “exonumia,” however, refers to numismatic items specifically apart from currency — meaning tokens, medals, and tickets. Coin collecting is a popular hobby, but there’s plenty of material for collectors of exonumia, too. People save old concert tickets, hold on to tokens and buttons, and preserve other memorabilia that qualifies as exonumia.