One of the major elements that help in making a topic or a news trending is hashtags and it is something that is used on almost all kinds of social media platforms as well. Although Google has used the same elements in Google+, it did not turn out to be successful for them and was killed. Although Youtube, which is a part of Google, is still using the same elements, it seems that Google is now again trying to experiment with new features using hashtags.
The company is trying to add and integrate hashtags in the cards that appear on Google Discover, which is somewhat very similar to what one can see on Youtube. The cards have a couple of hashtags showing up near the bottom of each card. The experiment by Google is mainly focused on making such cards more trending by using these hashtags, which can be used on social media, which will also help in displaying the cards.
The hashtag will be able to provide the users with more relevant cards, videos, and links for the same or similar content. For example, clicking on a hashtag like #hills will make Google show you similar content on hills that people are searching for right now and which is more relevant. The new feature is already live right now and can be used to discover new things. However, what Google really wants to achieve with the new feature is still unknown, neither have they revealed any details about it.