cdnjs is a free distributed JS library delivery service.
Hoefler&Co is a digital type foundry (font design studio) in Woburn, Massachusetts (formerly New York City), founded by type designer Jonathan Hoefler. Hoefler&Co designs typefaces for clients and for retail on its website.
jQuery CDN is a way to include jQuery in your website without actually downloading and keeping it your website's folder.
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.
Modernizr is a JavaScript library that detects the features available in a user's browser.
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.
Progressive Web Apps (PWAs) are web apps built and enhanced with modern APIs to deliver enhanced capabilities, reliability, and installability while reaching anyone, anywhere, on any device, all with a single codebase.
SEOmatic facilitates modern SEO best practices & implementation for Craft CMS 3.