The main purpose of using a fancy tree is a tree view/tree grid that allows to dynamically render powerful, user-friendly tree view, drag&drop, lazy loading, efficient and performant handling of large data sets.
CKEditor provides features to add images, mathematical formula, formatting of texts as per the needs, etc in questions.
The sunbird players is used to preview Question and Questionset.
Use Common Forms to define the dynamic layout of a page that contains fields and sections. What makes this dynamic is you can show/hide the sections & fields based on certain criteria, which currently is not possible with static page layouts.
Telemetry SDK is a standalone telemetry JS library allows to capture telemetry data.