I'm going to run through each of the languages, and give you some sample code for each.
PHP: PHP is used to program websites that can do things automatically. Take my website,
UberAAZ.com. When you access it, it accesses a database, gets my posts and the content of the sidebar, then displays it to you.
<?php
//this will display "Hello World" in the browser window
echo "Hello World";
?>
CSS: CSS is used to design pages. You might say "yes, but I can do that in HTML", and you'd be right, but the point of CSS is that if you want to change the design of your website by editing the style sheet you can do it all in one place.
<style type="text/css">
<!--
body,td,th {
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: small;
color: #000000;
}
body {
background-color: #FFFFFF;
}
-->
</style>
JavaScript: JavaScript is used to do some quite advanced things, such as displaying popups, asking for user input, doing things based on that input, etc. I really don't like this language though (my personal opinion) because if you use a browser that's not called Internet Explorer some of the more advanced stuff will look awful or just plain won't work.
<script language="text/javascript">
location.href="www.blah.com";
</script>
(code above moves to
www.blah.com)
Hope that helps,
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