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.
cdnjs is a free distributed JS library delivery service.
Handlebars is a JavaScript library used to create reusable webpage templates.
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.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Stripe offers online payment processing for internet businesses as well as fraud prevention, invoicing and subscription management.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.
Unpkg is a content delivery network for everything on npm.