HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Mapbox GL JS is a JavaScript library that uses WebGL to render interactive maps from vector tiles and Mapbox styles.
Mapbox.js is a JavaScript library provided by Mapbox for working with interactive maps and geospatial data.
Open Graph is a protocol that is used to integrate any web page into the social graph.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.