In the phpinfo.php page you can see the PHP version at the top of the file, and you can find the current version of MySQL.
You can also use phpinfo to check php settings like safe_mode and register_globals.
How? Create a file named 'phpinfo.php' in the public_html folder of your site and insert the following code:
<?php
phpinfo();
?>
Next, go to your browser and type:
http://yourdomain.com/phpinfo.php
Please replace "yourdomain.com" with your actual domain.