title: Method in the type is not applicable to arguments
body: <p>I'm a newbie working on a basic class creation tutorial and have been given the below instructions.</p>
  
  <pre><code>1) Create a new class called Book.
  2) Create fields for title, author, numPages, and isbn.
  3) Create a method called toString that appropriately describes the book.
  4) In the file, BookRunner.java:
    a) Declare two book variables
    b) Instantiate two book objects and set their fields.
    c) Print descriptions of the book objects using their toString methods.
  </code></pre>
  
  <p>So I've been working with two classes as instructed, and you can see the code below</p>
  
  <pre><code>public class Book {
      public String title;
      public String author;
      public String numPages;
      public String isbn;
  
      public void toString(String bookName) {
          String description = "Title:" + title + "Author"+ author + "Num. of pages" + numPages + "ISBN" + isbn; 
          System.out.println(description);
      }
  
  public class Ex1_BookRunner {
  
      public static void main(String[] args) {
          Book firstBook;
          Book secondBook;
  
          firstBook = new Book();
          secondBook = new Book();
  
          firstBook.title = "One Piece";
          firstBook.author = "Oda-Sensei";
          firstBook.numPages = "100";
          firstBook.isbn = "123456";
  
          secondBook.title = "Life of Megan Fox";
          secondBook.author = "Micheal Bay";
          secondBook.numPages = "200";
          secondBook.isbn = "098765";
  
          toString(firstBook);
          toString(secondBook);
      }
  }
  </code></pre>
  
  <p>My code shows no errors until the last two lines where I call the method <code>toString</code>.</p>
  
  <p>I get the error below </p>
  
  <pre><code>The method toString() in the type Object is not applicable for the arguments (Book)
  </code></pre>
  
  <p>Am I making some fundamental error somewhere in my method declaration? I've looked at other posts on SO with the same question but I have trouble understanding the explanations given because they mostly cover code syntax I haven't learnt yet.</p>
  
  <p>Any help is appreciated :)</p>