I hope this certificate review is providing you the detailed information in a simple form you where looking for.
Certified Site Metrics are metrics that are directly-measured from the website instead of estimated.
Thumbnails are automatically generated from the videos.
"Categories" is just a list of the most popular search queries entered by surfers.
All of the videos embeded on our site are hosted by websites that are not under our control.
The linked videos are automatically gathered and added into our system by our spider scripts.
It was owned by several entities, from Internet Service Europe*) to Internet Service Europe B.