Remember the "Moments" tab on Twitter's app? It's gone now, replaced by an "Explore" section that combines trending topics, and a bit of those Moments collections of popular stories, and the app's search function.
Between the lines: When Twitter released Moments in October 2015, it was supposed to be the next big thing on Twitter, a way for users to follow the biggest news stories on the social network. But it didn't make a huge splash among users. And now Moments has been demoted from having its own tab.
What it means: This is yet another attempt by Twitter to make it easy for users to discover all the news and interesting content in one place. Twitter is undeniably filled with interesting and important tweets for its users, but finding them has been a challenge. Other attempts have included the "While you were away" feature and the injection of tweets from people the user doesn't follow (but may want to).