The HashSet implements set logic in its many instance methods. We use methods such as Union on different HashSets to solve problems. This makes some programs simpler.
1. HashSet : Hashset is an optimized set collection. It helps eliminates duplicate strings or elements in an array. It provides a simple syntax for taking the union of elements in a set. This is performed in its constructor.
2. SortedSet : Sortedset is an ordered set collection. We have many elements and want to store them in a sorted order and also eliminate all duplicates from the data structure. The SortedSet is part of the System.Collections.Generic namespace.