what is vendor/autoload.php?

[wogho]

require DIR . '/vendor/autoload.php;

[root@instance-1 markme-silex]# php console.php orm:schema-tool:create --force PHP Warning: require(/root/markme-silex/vendor/autoload.php): failed to open stream: No such file or directory in /root/markme-silex/console.php on line 15 PHP Fatal error: require(): Failed opening required '/root/markme-silex/vendor/autoload.php' (include_path='.:/usr/share/pear:/usr/share/php') in /root/markme-silex/console.php on line 15