cdnjs is a free distributed JS library delivery service.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PHP is a general-purpose scripting language used for web development.
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.
WP Fastest Cache is one of a number of plugins for WordPress designed to accelerate the performance of your website.
Yoast SEO is a search engine optimisation plugin for WordPress and other platforms.