What are the languages used to create the functions on wake.com [on hold]

I would like to know what are the languages used to create the functions that you can see on this page of the website http://ift.tt/2qTUqpk (Other than HTML and CSS) I am specifically looking for how to create the function that has the title "Feedback in one place, next to the work".

Also I would really appreciate if someone could tell me what is the proper name for this function since I have tried searching for "feedback scripts", "captions on images", etc but without luck.