cdnjs is a free distributed JS library delivery service.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
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.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Squarespace Commerce is an ecommerce platform designed to facilitate the creation of websites and online stores, with domain registration and web hosting included.
Squarespace provides Software-as-a-Service (SaaS) for website building and hosting, and allows users to use pre-built website templates.