How did we iterate through in Prompter class?

import java.io.Console; //this line of code is needed to import the method that prompts for user input

/* Let's first get her prompter able to accept guesses.
    To do this we have to add a constructor that accepts the game logic object 
   (which we have already created) */
public class Prompter {
  private Game mGame; //we are storing the game logic in a private variable called mGame


  public Prompter(Game game) {
    Game = game;
  }

// then Craig adds a prompter to get the guess from the user via a console prompt
  public boolean promptForGuess() {
    Console console = System.console();
    // this is the method that prompts for user input requiring import java.io.Console

   String guessAsString = console.readLine("Enter a letter: "); 
   //stores prompted user input as a String named guessAsString

  char guess = guessAsString.charAt(0);
  /* This is likely where you got confused. By nature of the prompt design the user could 
enter multiple letters such as 'xyz', but we're asking them for one character as a guess. 
How do we simplify this ad dodge errors? By appending .charAt(0) to whatever the user 
input is, the program will only take the first character they enter as their guess - all of the 
others will be ignored. */

  return mGame.applyGuess(guess);
  /* this will return true or false if the first character of the user guess equals a character 
from the compared to string from hangman.java (**The iteration method of which is defined in the game logic!!!**) */
  }
}

public class Test {

   public static void main(String args[]) {
      String s = "Strings are immutable";
      char result = s.charAt(8);
      System.out.println(result);
   }
}

public class Hangman {

    public static void main(String[] args) {
        // Enter amazing code here:
      Game game = new Game("treehouse");
      Prompter prompter = new Prompter(game);
     //inject game logic

     //set outputs based on game logic
      boolean isHit = prompter.promptForGuess();
      if (isHit) {
        System.out.println("We got a hit!");
      } else {
        System.out.println("Whoops that was a miss");
      }
    }
}