How does X decide which trending topics to display for each user, and how does this differ from the way Twitter Trends once operated?
How does X decide which trending topics to display for each user, and how does this differ from the way Twitter Trends once operated? Trending topics on X no longer represent a single global conversation. Instead, each user sees trends shaped by personal interests, behavior, location, and interaction history—making trends feel different for everyone. This is a major departure from Twitter’s older trend model, which focused on raw volume and geographic spikes rather than personal relevance. 1. How Twitter Trends originally worked Twitter Trends were built around velocity-based detection. The system measured how quickly a topic, hashtag, or phrase was mentioned within a short time window, then ranked it based on geographic concentration. If thousands of users in a region mentioned the same phrase suddenly, it trended—regardless of whether the topic was relevant to most users individually. ...