With a corporate or business-related website, there are several advantages to being able to remove the .php file extension from any links to PHP pages on your web server.
1. It looks much cleaner and professional to have yourdomain.com/products instead of yourdomain.com/products.php
2. It's much easier from coding perspective to be able to accomplish this with files, rather than having to create lots of sub-directories with index.php files.
3. It's easier to hide the server-side technology that you're using, to prevent hacker attacks.
So, if you add one of the following two code options to your .htaccess files, you can link to your files without the .php extension. For example, you could link to /products instead or /products.php
AddHandler server-parsed .php SetHandler application/x-httpd-php AddHandler application/x-httpd-php .php
RewriteEngine On RewriteRule ^[^.]+$ - [T=application/x-httpd-php,L]