1) The document discusses the use and popularity of hashtags on social media platforms like Twitter. It explores how hashtags are used to group related tweets on a topic and how some hashtags gain widespread usage while others remain niche. 2) The popularity of hashtags can be predicted based on how they spread through social connections on platforms like Twitter. Newly created hashtags that are used to discuss emerging topics or events have the potential to take off if influential users help spread them. 3) The origins of the hashtag can be traced back to IRC chat, but it was Twitter that helped popularize its use by making hashtags clickable links to view other tweets containing that tag. Now hashtags are an essential way