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.
Keap offers an email marketing and sales platform for small businesses, including products to manage customers, customer relationship management, marketing, and ecommerce.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Particles.js is a JavaScript library for creating particles.
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 Engine is a website hosting provider.