Hashtags are used by Twitter users to make it easier to search for tweets about specific topics and events. A hashtag consists of a word or code which is preceded by a “#” which helps denote what the tweet is about. Think of it as tweet-metadata.  Hashtags allows specific tweets to be searchable and discoverable along with other tweets that contain the same hashtag.

For example:

#ala2009 : American Library Association 2009 Annual Meeting

#ohiostate : No explanation needed

Hashtags have become popular as a tool to track updates in real time especially during conferences or community events. Hashtags have also come into their own during crises and disasters, such as the #iranelection.

One issue with hashtags is that there is no hashtag registration or authority. Tags are ‘claimed’ by a group simply be using it. However, a single tag could also refer to several topic threads, a common occurrence is with conference hashtags. For example, #mla09 was used for annual meetings of the Maryland Library Association and the Medical Library Association which met within days of each other. A startup called Hashtag Directory is an attempt at a registration service.

A service that tracks tags currently in use is #Hashtags.

Some hashtags can be confusing at times because there’s little context for them. For example, how long would it take to figure out #tdf was the hashtag for the Tour de France? One source than can help identify hashtags is called  What The Hashtag, a community-built encyclopedia that provides detailed definitions and context of hashtags and any trending topics. The site also provides stats, real-time stream monitoring, and charts.

Finally, hashtags can also be used by spammers and marketers to artificially boost the use of the tag so that is seen as a tending topic, which then drives more traffic. A recent example of this was an Apple Macbook giveaway based on posts which include the hashtag #moonfruit.  (see, now you will go there and create even more interest)

While hashtags aren’t a perfect solution they are getting the job done. That is until a librarian gets involved and creates a hashtag authority file, registration system, and standard naming conventions.

-Eric Schnell