Why JavaScript Data Types are Dynamic?

Javascript Web Development Front End Technology

JavaScript also has dynamic types. That would mean the same variable used for holding different data types in JavaScript.

Example

<html>
   <head>
      <script>
         var val;
         val = "Amit";
         document.write("String: "+val);

         val = 20;
         document.write("<br>Number: "+val);

         val = 40.90;
         document.write("<br>Number with decimals: "+val);
      </script>
   </head>
   <body>
   </body>
</html>