Warning: Use of undefined constant lang - assumed 'lang' (this will throw an Error in a future version of PHP) in /index.php on line 2

Fatal error: Uncaught Error: Call to undefined function mysql_connect() in /backend/functions/start.php:3 Stack trace: #0 /index.php(25): loguj() #1 {main} thrown in /backend/functions/start.php on line 3