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.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PHP is a general-purpose scripting language used for web development.
Typekit is an online service which offers a subscription library of fonts.
Vimeo is a video hosting, sharing and services platform. Vimeo operation an ad-free basis by providing subscription plans.