I have being doing this for awhile already and now decided to share it with the world.
To built a website I use about 5-6 PHP pages to make up one PHP page. Since PHP is a web developing code, I would talk a little bit about it.
Before I get into the tricks or tips I would say a few of the features that PHP has... It can INCLUDE files into other files and STORE values into variables and you can call on them multiple times making it easy to change multiple stuff that are the same throughout the site... such as the web master's email.
Here is how you INCLUDE files into other files...
<?php include_once('filename.php'); ?>
The file could be any web file type... not only PHP, but it could be HTM, HTML, CSS, PERL, etc. etc.
Here is how you STORE values into variables...
<?php
$webmaster_email = 'my_email@my_site.com';
$site_title = 'site_title';
?>
And below is how you CALL on them...
<?php echo $webmaster_email; ?>
I store values into variables in one file and name that file as "site_config.php", than I put everything starting from "<html>" to "<body>" into another PHP file which I like to call "header1.php". Then I store the logo into another file and I like to call that file as "header2.php". And than I store the footer with the ending tags (</body> </html>) into another file and I like to call that file as "footer.php".
Than I include those files into "index.php" and type in the content where the main content would be... a sample of one of my main pages is shown below...
<?php include_once('includes/header1.php'); ?>
<div id="wrap">
<?php include_once('includes/header2.php'); ?>
<?php include_once('includes/leftContent.php'); ?>
<div id="rightContent">
<div class="content"><p>Main Content</p></div>
<div class="mainContent">
<p>My Main Content</p>
</div>
<div class="spacer6"></div>
<div class="content"><p>Updates/Important News</p></div>
<div class="mainContent">
<p>Important News</p>
</div>
<?php include_once('includes/footer.php'); ?>
It's an easy trick that may be hard to explain.