Amazon S3 or Amazon Simple Storage Service is a service offered by Amazon Web Services (AWS) that provides object storage through a web service interface.
cdnjs is a free distributed JS library delivery service.
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.
Leaflet is the open-source JavaScript library for mobile-friendly interactive maps.
Mailchimp is a marketing automation platform and email marketing service.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Unpkg is a content delivery network for everything on npm.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.