What is the difference between an enumerator and an iterator in Java?

Enumerator (Enumeration) and Iterator are interfaces for traversing collections in Java, but there are differences between them:

• Enumeration is an outdated interface that appeared in early versions of Java. Methods: hasMoreElements() and nextElement(). It does not support element removal.
• Iterator is a more modern interface introduced in Java 1.2. Methods: hasNext(), next(), and remove(). It allows safe removal of elements during traversal.

Example of using Iterator:

List<String> list = new ArrayList<>();
list.add("a");
list.add("b");
Iterator<String> it = list.iterator();
while (it.hasNext()) {
    String s = it.next();
    if (s.equals("a")) {
        it.remove();
    }
}