If we want to create a quick gallery of files/pictures, it is quite a pain to do so manually. And since this is some code I'm always reusing I thought I might share it here with everyone else:

Let's suppose we are in the base directory (www.mysite.com/gallery.php) and the pictures are in a folder named pictures (www.mysite.com/pictures/), open gallery.php and where you want the pictures to appear, use this code:

$handle = opendir(dirname(realpath(__FILE__)).'/pictures/');
		while($file = readdir($handle)){
			if($file !== '.' && $file !== '..'){
				echo '<img src="pictures/'.$file.'" border="0" />';
			}
		}

This code is really easy to understand, we first define a variable "$handle", which will contain the handle to the absolute path of the folder (I always go for absolute paths since I find them much safer)
dirname(realpath(__FILE__)) returns the absolute path to the current file (gallery.php) and then we add to the end of it /pictures/

Then, we loop through all the files in the directory, that simple if statement I used is to prevent some the function returning . or .. as file names sometimes. We then display the image in standard html

Take care!
Alex