Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
Calendly is an app for scheduling appointments, meetings, and events.
cdnjs is a free distributed JS library delivery service.
fullPage.js a jQuery and vanilla JavaScript plugin for fullscreen scrolling websites.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
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.
JSDelivr is a free public CDN for open-source projects. It can serve web files directly from the npm registry and GitHub repositories without any configuration.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.