Craft CMS is a content management system for building bespoke websites.
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.
Polyfill is a service which accepts a request for a set of browser features and returns only the polyfills that are needed by the requesting browser.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.