The feature related content gathers automatically content that has the same labels and displays it on the details page of another asset.

The advantage of labels is that they are not visible to the customers. You can freely introduce content categorisation that fits your streaming service.
The order of the content in the related content section is based on the label matches. The more label match with each other the higher the ranking.

If you want to use the feature read here how to activate and manage it.