What is the internal organization of data underlying the Map structure?

The underlying structure of Map in Java is based on data organization, which depends on the specific implementation:

• HashMap — uses an array of buckets, each containing a linked list or a tree (since Java 8) to store key-value pairs. Keys are hashed to determine the bucket index.

• TreeMap — implemented based on a red-black tree, which provides ordered storage of keys.

• LinkedHashMap — extends HashMap, maintaining insertion order of elements using a linked list.

Thus, the basic structure is either a hash table with chains (HashMap) or a balanced tree (TreeMap).