<script type="text/javascript">
function whichname()
   {
   var bname = navigator.appName;
   alert("You are using " + bname);
   }
</script>
						Some time you can have situation that you have to need the show the browser message to user then you will write this code.
						----------------------------------------------
<script type="text/javascript">
var browsrName = navigator.appName;
if (browsrName.search(/netscape/i) == 0)
   {
   alert('you are using netscape');
   }
else if (browsrName.search(/microsoft/i) == 0)
   {
   alert('you are using internet explore');
   }
else
   {
   alert('you are using any other browser');
   }
</script>
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