cdnjs is a free distributed JS library delivery service.
Google AdSense is a program run by Google through which website publishers serve advertisements that are targeted to the site content and audience.
Leaflet is the open-source JavaScript library for mobile-friendly interactive maps.
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.
Vue.js is an open-source model–view–viewmodel JavaScript framework for building user interfaces and single-page applications.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.