Apache is a free and open-source cross-platform web server software.

Cloudflare is a web-infrastructure and website-security company, providing content-delivery-network services, DDoS mitigation, Internet security, and distributed domain-name-server services.

reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.

WooCommerce is an open-source ecommerce plugin for WordPress.

Contact Form 7 v5.1 dropped support for reCaptcha v2 along with the [recaptcha] tag December 2018. This plugin brings that functionality back from Contact Form 7 5.0.5 and re-adds the [recaptcha] tag.

Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.

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.

Yoast SEO is a search engine optimisation plugin for WordPress and other platforms.

MySQL is an open-source relational database management system.

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.

YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.

Google Analytics is a free web analytics service that tracks and reports website traffic.

PHP is a general-purpose scripting language used for web development.

jQuery UI is a collection of GUI widgets, animated visual effects, and themes implemented with jQuery, Cascading Style Sheets, and HTML.

Contact Form 7 is an WordPress plugin which can manage multiple contact forms. The form supports Ajax-powered submitting, CAPTCHA, Akismet spam filtering.

Query Migrate is a javascript library that allows you to preserve the compatibility of your jQuery code developed for versions of jQuery older than 1.9.

cdnjs is a free distributed JS library delivery service.