Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Plesk is a web hosting and server data centre automation software with a control panel developed for Linux and Windows-based retail hosting service providers.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
Redux Framework is a modular PHP library that allows developers to create customisable settings panels and controls for WordPress projects, providing a consistent user interface for managing options and settings.
W3 Total Cache (W3TC) improves the SEO and increases website performance and reducing load times by leveraging features like content delivery network (CDN) integration and the latest best practices.
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.