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You are free to put as many scripts into a single document as you like, using multiple script tags.
              A script embedded in HTML with the <script> tag uses the following format:

                  <html>

                  <head>
                  <script type=”text/javascript”>
                  -------Type your JavaScript Code here------------
                  </script>
                  </head>

                  <body>
                  --------Type your HTML code here------------------
                  </body>

                  </html>
              Scripts can be used in four locations across the HTML content and so JavaScript scripts are categorized as
              inline, internal and external script:
              1.  Page body: When the page is loaded in the browser, the output appears as part of the HTML content.
              2.  Page header: The code is written in the form of a function (a collection of JavaScript statements that are
                 handled as a single unit) and referenced to in another script on the same page.
              3.  Within the HTML tag: When JavaScript is used as an event handler (explained later in the chapter), it
                 interacts with HTML elements.

              4.  As an external file: In this scenario, the JavaScript code is stored in a .js file. In the script tag, this file is
                 included.

                3.2 JAVASCRIPT VARIABLES

              A JavaScript variable (also known as an identifier) is a storage location in the memory. The keyword var can be
              used to declare variables in JavaScript. When a variable is given a value, the equal to (=) symbol is used. Users
              have the option of declaring variables separately and subsequently assigning values to them, or declaring and
              initialising variables at the same time.

              Example:

                  <html>

                  <body>
                  <script>
                  var p = 25;
                  var q = 35;

                  var prod=p*q;
                  document.write(“The product is “+prod);
                  </script>
                  </body>

                  </html>



                182   Touchpad Web Applications-XII
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