Contact Form 7 is an WordPress plugin which can manage multiple contact forms. The form supports Ajax-powered submitting, CAPTCHA, Akismet spam filtering.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Priority Hints exposes a mechanism for developers to signal a relative priority for browsers to consider when fetching resources.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
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.