Apache is a free and open-source cross-platform web server software.
Contact Form 7 is an WordPress plugin which can manage multiple contact forms. The form supports Ajax-powered submitting, CAPTCHA, Akismet spam filtering.
PHP is a general-purpose scripting language used for web development.
Polylang is a WordPress plugin which allows you to create multilingual WordPress site.
Priority Hints exposes a mechanism for developers to signal a relative priority for browsers to consider when fetching resources.
Varnish is a reverse caching proxy.
WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. Features include a plugin architecture and a template system.
Zakra is flexible, fast, lightweight and modern multipurpose WordPress theme that comes with many starter free sites.