HashSet vs LinkedHashSet

Question

What is the difference between them? I know that

A LinkedHashSet is an ordered version of HashSet that maintains a doubly-linked List across all el

Answer 1

LinkedHashSet's constructors invoke the following base class constructor:

HashSet(int initialCapacity, float loadFactor, boolean dummy) {
  map = new LinkedHashMap(initialCapacity, loadFactor);
}

As you can see, the internal map is a LinkedHashMap. If you look inside LinkedHashMap, you'll discover the following field:

private transient Entry header;

This is the linked list in question.