Collectible coins, particularly those issued by the United States of America (USA), encompass a wide variety of types, including currency, commemorative coins, and proof sets. The term "1 Roll" refers to a standard quantity of coins, typically containing 50 coins of the same denomination, often sought after by collectors. The year 2009 is significant for several coin issues, such as the Lincoln Bicentennial pennies, which featured design changes and represent a key year in U.S. numismatics. Collectors value such coins based on their rarity, condition, historical significance, and demand within the market.