Date Added: Aug 2009
If you've used Twitter for more than a couple of hours, you've probably already seen a tweet or two containing a word with the hash symbol ("#") attached to it. That's what Twitter users call a "Hashtag," and at any given time at least one of them can usually be found among the trending topics on Twitter. But what exactly is a hashtag? Hashtags are essentially a simple way to catalog and connect tweets about a specific topic. They make it easier for users to find additional tweets on a particular subject, while filtering out the incidental tweets that may just coincidentally contain the same keyword.