Collectible coins encompass various types, including commemorative coins, bullion coins, and circulation coins that are no longer in production. In the United States, the Kennedy Half Dollar, minted since 1964, features the profile of President John F. Kennedy and is a popular collectible due to its historical significance and design. The 1999 Kennedy Half Dollar was produced as part of the ongoing circulation of this coin, which has often been sought after by collectors, particularly in uncirculated or proof conditions. Collectors often seek specific years, mint marks, and conditions to enhance the value of their collections.