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.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Simple parallax scrolling effect.
Polylang is a WordPress plugin which allows you to create multilingual WordPress site.
Slider Revolution is a flexible and highly customisable slider.
Configurable JavaScript/CSS spinner that can be used as a resolution-independent loading indicator
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.
WPBakery is a drag and drop visual page builder plugin for WordPress.
Yoast SEO is a search engine optimisation plugin for WordPress and other platforms.