<html>
  <head><title>Hello World</title></head>
  <body>
    <script type="text/javascript">
      document.write("Hello World)
    </script>
  </body>
</html>
Examples 14-4 to 14-7 are non-runnable illustrations of error messages
<script>
function product(a, b)
{
    return a*b
}
</script>
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<script>
  n = '838102050'        // Set 'n' to a string
  document.write('n = ' + n + ', and is a ' + typeof n + '<br>')

  n = 12345 * 67890;     // Set 'n' to a number
  document.write('n = ' + n + ', and is a ' + typeof n + '<br>')

  n += ' plus some text' // Change 'n' from a number to a string
  document.write('n = ' + n + ', and is a ' + typeof n + '<br>')
</script>
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<script>
  function product(a, b)
  {
    return a*b
  }
</script>
<script>
  function test()
  {
        a = 123               // Global scope
    var b = 456               // Local scope
    if (a == 123) var c = 789 // Local scope
  }
</script>
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<script>
  test()

  if (typeof a != 'undefined') document.write('a = "' + a + '"<br />')
  if (typeof b != 'undefined') document.write('b = "' + b + '"<br />')
  if (typeof c != 'undefined') document.write('c = "' + c + '"<br />')

  function test()
  {
     a     = 123
    var b = 456

    if (a == 123) var c = 789
  }
</script>
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<html>
  <head>
    <title>Link Test</title>
  </head>
  <body>
    <a id="mylink" href="http://mysite.com">Click me</a><br />
    <script>
      url = document.links.mylink.href
      document.write('The URL is ' + url)
    </script>
  </body>
</html>
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<script>
  function $(id)
  {
    return document.getElementById(id)
  }
</script>
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<html>
  <head><title>Hello World</title></head>
  <body>
    <script type="text/javascript">
      document.write("Hello World")
    </script>
    <noscript>
      Your browser doesn't support or has disabled JavaScript
    </noscript>
  </body>
</html>
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<html>
  <head><title>Hello World</title></head>
  <body>
    <script type="text/javascript"><!--
      document.write("Hello World")
    // -->
    </script>
  </body>
</html>
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