CloudLinux PHP Selector is a tool that allows users to select and switch between multiple PHP versions and configurations on a single server. It enables web hosts to provide their clients with the ability to choose the PHP version and modules that suit their website requirements. The PHP Selector also enables users to enable/disable specific PHP extensions, change PHP settings, and manage the PHP-FPM pool configuration. The tool supports a wide range of PHP versions, including PHP 5.2, 5.3, 5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3, and 7.4, allowing web hosts to accommodate different applications and scripts running on their servers.