cdnjs is a free distributed JS library delivery service.
DigitalOcean Spaces is a cloud-based object storage service provided by DigitalOcean, a cloud infrastructure provider. It allows users to store and retrieve large amounts of data, such as images, videos, audio files, backups, and logs, using a simple RESTful API or a web-based graphical user interface (GUI).
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
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.
MathJax is a cross-browser JavaScript library that displays mathematical notation in web browsers, using MathML, LaTeX and ASCIIMathML markup.
Netlify providers hosting and server-less backend services for web applications and static websites.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.