What is a Set in Java?

A Set in Java is specifically designed to store a collection of unique elements, meaning it does not allow duplicate entries. This characteristic makes Sets particularly useful in scenarios where the uniqueness of items is paramount. For example, if you need to maintain a list of user IDs or unique identifiers, a Set ensures that each entry is only present once, enhancing data integrity.

In Sets, the elements are not stored in any particular order, which distinguishes them from other types of collections like Lists. Furthermore, Sets do not provide key-value pair storage, which is a feature associated with Maps. It is also important to note that Sets do not permit duplicates, which is a fundamental part of their functionality, making them distinct from collections that allow such repetitions. This makes the choice that identifies a Set as a collection with unique elements the only correct understanding of what a Set is in Java.