[JavaScript]
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Overview: Sample Script

To get some sense of the forest before we start sorting out the trees, let's look at a simple JavaScript and examine its components:

	<script language="JavaScript">
	<!--
	/* This script tells displays the browser name and version being used.
	It is more complicated and less efficient than it should be,
	for the sake of clarity.
	Legend:
	Red = keyword
	Blue = variable
	Purple = operator
	Olive = function
	Teal = control structure
	Black = object
	Navy = property
	Fuchsia = method
	Green = comment
	Note that these colors will only be visible if your
	browser supports Cascading Style Sheets
	*/
	/* set variables equal to browser
	name and version and add another equal
	to the integer portion of "version" */
	var browser=navigator.appName; 
	var version=navigator.appVersion; 
	var ver1=version.substring(0,1); 
	/* Write the identity of the browser and version */
	document.write("Your browser is " + browser + "<br>");
	document.write("The version is " + version + "<br>");
	// check for Netscape 4+
	if ((browser == "Netscape")  && (ver1 >= 4)) 
	{
	/* write a message to the Netscape crowd */
	document.write("<b>You are using a great browser!</b>"); 
	}
	else {
	checkIE()
	}
	
	function checkIE(){
	// check for IE 4+
	if ((browser == "Microsoft Internet Explorer") && (ver1 >= 4)) 
	{
	/* write this to the IE crowd */
	document.write("<b>You are using a terrific browser!</b>"); 
	}
	else {
	tellUser(); // otherwise, go to this function
	}
	}
	/* the functions writes a different message to the uncool */
	function tellUser() {
	document.write("Your browser is old!");
	}
	 -->
	</script>
	

We'll take a quick look at these components in the next page.

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