title: bluej Try/catch/exception
body: <p>I'l post my three question where the questions occur aswell in the code, aswell as post it up here.</p>
  
  <p>Q 1 what are threads and how do i use them?<br>
  Q 2 how do 'try' / 'catch' work?
  Q 3 what is the exception? see code.</p>
  
  <p>Thank you in advance :)</p>
  
  <pre><code>public void start() {
    //  Question 1: What are these threads and how do i implement them?
    Thread frameTiming = new Thread (this);
    frameTiming.start ();
  }
  
  public void run() {
    while (true) {
      xleft-=10;
      yleft-=10;
      xleft2+=10;
      yleft2+=10;
      i-=5;
      repaint();
      //  Question 2: what does try/catch do?
      try {
        Thread.sleep(40);
      // question3: what does this exception do exactly? :0
      } catch (Exception e) {
      }
  
  }
  </code></pre>