The previously described class, HashSet, can be understood as a dictionary that stores only keys, without values. So, if there is the SortedDictionary class, maybe there is also the SortedSet class? Indeed, there is! However, can a set be "sorted"? Why is the "sorted" word written with quotation marks? The answer is simple—by definition, a set stores a collection of distinct objects without duplicated elements and without a particular order. If a set does not support order, how can it be "sorted"? For this reason, a "sorted" set can be understood as a combination of HashSet and SortedList, not a set itself.

The "sorted" set can be used if you want to have a sorted collection of distinct objects without duplicated elements. The suitable class is named SortedSet and is available in the System.Collections.Generic namespace. It has a set of methods, similar to those already described in the case of the HashSet class, such as UnionWith, IntersectWith, ExceptWith, SymmetricExceptWith...