Объясните что происходит в методе Save и Download

import java.io.*;
    
public class Serialize implements Serializable {

  public static void Save(Bank bank) throws IOException {
    File out1 = new File("C:\\Users\\sveta\\IdeaProjects\\untitled\\src\\Lr3\\file.dat");
    FileOutputStream Out1 = new FileOutputStream(out1);
    ObjectOutputStream objectOutput = new ObjectOutputStream(Out1);
    objectOutput.writeObject(bank);
    Out1.close();
    objectOutput.close();
  }


  public static void Download(Bank bank) throws IOException, ClassNotFoundException {
    FileInputStream In1 = new FileInputStream("C:\\Users\\sveta\\IdeaProjects\\untitled\\src\\Lr3\\file.dat");
    ObjectInputStream objectInput = new ObjectInputStream(In1);
    Bank bank1 = (Bank)objectInput.readObject();
    String name = bank1.getName();
    int accounts = bank1.getSize();
    int atm = bank1.getATMs();
    System.out.println("Банк: " + name);
    System.out.println("Количество счетов: " + accounts);
    System.out.println("Количество Банкоматов: " + atm);
    In1.close();
    objectInput.close();
  }
}