cdnjs is a free distributed JS library delivery service.
Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Modernizr is a JavaScript library that detects the features available in a user's browser.
OneTrust is a cloud-based data privacy management compliance platform.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Varnish is a reverse caching proxy.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.