cdnjs is a free distributed JS library delivery service.
Google Maps is a web mapping service. It offers satellite imagery, aerial photography, street maps, 360° interactive panoramic views of streets, real-time traffic conditions, and route planning for traveling by foot, car, bicycle and air, or public transportation.
Ionicons is an open-source icon set crafted for web, iOS, Android, and desktop apps.
RequireJS is a JavaScript library and file loader which manages the dependencies between JavaScript files and in modular programming.