Item could be obtained by purchasing in the store, found randomly during exploration, daily rewards, etc.
Dragon feed fall into this category.:Food
Equipment could be equipped by dragons. When equipped they raise dragon's status. Claws, feathers, charms, etc. could be found in this category.;Accessories
Gems Can be equipped by dragons. The maximum is 5 gems for each dragon;Gems
Stuff used to make your dragons stronger:Material
All other items, which doesn't belong to any other categories, falls into this category. Others