How can PHP be used to list the files in a directory and display them as clickable links without file extensions?

To list files in a directory and display them as clickable links without file extensions using PHP, you can use the `scandir()` function to retrieve the list of files in the directory, loop through the files, and then use `pathinfo()` function to get the filename without the extension. Finally, you can display the filenames as clickable links in HTML format.

<?php
$dir = "your_directory_path_here";
$files = scandir($dir);

foreach($files as $file) {
    if($file != '.' && $file != '..') {
        $filename = pathinfo($file, PATHINFO_FILENAME);
        echo "<a href='$dir/$file'>$filename</a><br>";
    }
}
?>