Hard Candy
Some of the original hard candy that was made was for medicinal purposes. Peppermint and other herbs would be added to a sugar and water combination. These were the first lozenges, and were for treating colds and coughs.
Nowadays hard candy is mostly made just to be tasty. There are many different flavors and varieties, some of which have been around for a long time. If you are interested in something old fashioned, you can get hard pieces of candy that is made in traditional ways from old recipes.
Hard candy has great longevity in multiple ways. One reason it has been so popular is that it lasts for a very long time if it is kept dry. It also lasts a long time when you are eating it. Hard candy dissolves slowly, so even a small piece of candy can last up to half and hour or so.