Questions concerning include('inc/header.php') and include('inc/footer.php');

If you keep going in the php track, Randy talks about creating a config.php file in the includes folder for creating constants. Constants are like variables that you set once and do not change. Generally this information would be kept in there as to stick with the don't repeat yourself model (DRY). Constants are set up by using this:

define( 'CONSTANT_IN_CAPS', '/folderlocation/' ); //folder location is based on your sites location in the server htdocs folder. If it is not in subfolder then you can just use '/'. Capital letters should be used for the name. 

Inside the config.php file you can place this:

<?php

    define('BASE_URL', '/folder/');

    define('ROOT_PATH', $_SERVER['DOCUMENT_ROOT' .  '/folder/' );

To use this now, go back into your files and include the path to your config file on the top of any page you want to use it for for any includes on that page. To use it for includes type this:

<?php 
      include(ROOT_PATH . 'inc/filename' );
?>

Next replace any image links and relative links to use the BASE_URL constant. for instance if there is a picture called image.jpg located in an img folder in the main htdocs location, change the source from <img src="img/image.jpg"> to this:

<img src="<?php echo BASE_URL; ?>img/image.jpg">

The reason for doing this is so that if you ever have to migrate your site to a different folder or to put it online, all you will need to change is the config file and all your relative paths will work the same. Be sure to continue on in the php course to see this in more detail and maybe even do a google search on php constants. Best of luck!

You can include from the root, you can find out what you root is by using $_SERVER['DOCUMENT_ROOT']; Here's an example:

<?php 
   $path = $_SERVER['DOCUMENT_ROOT'];
   $path .= "/common/header.php";
   include_once($path);
?>

Great answer Chris, thank you.