Explain the concept of immutable collections and their main advantages.

Immutable collections are collections whose contents cannot be changed after creation. In Java, these include collections created using methods like List.of(), Set.of(), Map.of(), or wrappers from Collections.unmodifiableList().

Main advantages of immutable collections:

• Thread safety: Immutable objects can be safely used in multithreaded environments without synchronization.
• Predictability: The state of the collection does not change, simplifying debugging and understanding of the code.
• Error prevention: Prevents accidental modification of data.
• Optimizations: Some implementations can use internal optimizations knowing that data will not change.

Example of creating an immutable list:

List<String> list = List.of("A", "B", "C");
// list.add("D"); // will throw UnsupportedOperationException

Using immutable collections promotes cleaner and safer code.