final — keyword. finally — block. finalize — method (deprecated).Vivid analogy: final is like a sealed envelope — once sealed, contents cannot change. finally is like a cleanup crew — no matter what happens at a party, the crew always cleans up. finalize() is like a last will — called by GC before disposing, but unreliable.Why it matters: final enforces immutability at compile time. finally is essential for resource cleanup. finalize() is deprecated — use AutoCloseable instead.javafinal int MAX = 100;// MAX = 200; // Compile error!try (BufferedReader br = new BufferedReader(new FileReader("data.txt"))) { String line = br.readLine();} catch (IOException e) { e.printStackTrace();} // Resources auto-closed — no finally needed!public class MyResource implements AutoCloseable { @Override public void close() { System.out.println("Cleaned up!"); }}- final — constant reference/non-overridable.- finally — guaranteed cleanup.- finalize() — deprecated.