What Makes a Good Hashtag? It’s Not Science

If you spend any time on Twitter, you’ve probably seen a hashtag — it’s a keyword with a number sign in front of it, which is used to refer to an ongoing conversation of some kind. Hashtags can occasionally take off and become trends that dominate the Twitter-sphere for periods of time, and that’s exactly what happened recently with the “#lessambitiousmovies” tag. But how do these trends evolve, and how long do they last? The Twitter media blog did a forensic analysis of the latest example, but the really interesting thing is just how random — and short-lived — these Twitter storms can be. It’s much more of an art (or barely-controlled chaos) than it is a science.

As Liz Gannes noted in a piece last year, the first tweet with a hashtag in it came from Chris Messina — then a consultant and now the open-web advocate at Google (s goog). They soon came to be used for any ongoing conversation about a topic, and really took off during the San Diego fires of 2007. As Liz pointed out, most conferences now make coming up with a hashtag part of their repertoire, so that they can track discussion, and there are recurring tags such as the “follow Friday” or #ff tag.

Twitter’s analysis showed that the sarcastic movie discussion (which included entries like “A Funny Dream on Elm Street” and “Texas Chainsaw Repairman”) started with a tweet from Toronto-based graphic designer Rob McCallum, who posted “Scott Pilgrim Vs. The Room” with the hashtag #lessambitiousfilms on January 4 (he told me he likes to try ideas out on Twitter). A graph of tweets per minute shows that the volume of tweets with that tag climbed at a fairly rapid pace, but then at some point during the wee hours of January 5th a new variation took off: #lessambitiousmovies suddenly shot to prominence, and quickly had orders of magnitude larger numbers of tweets per minute than the original tag.

Robin Sloan of Twitter’s media team notes that the new tag likely took off because it got retweeted by several prominent users of the service, including Lizz Winstead, co-creator of the popular comedy talk show The Daily Show and Alexis Madrigal of The Atlantic. But one of the things that’s interesting about the graph is that the two hashtags co-existed for so long — and some people, including Winstead, actually posted tweets with both. Why did it change? Who knows. The real lesson is that Twitter community decides what a hashtag is going to be, not the person who created it, and to some extent it is unpredictable.

The other thing that seems obvious from the graph is that even the most popular hashtag has a short life-span, as Michael Sippey also notes in a blog post about the Twitter graph. Sloan describes how once the hashtag had begun to rapidly decline — something that took only a few hours from its peak of 17 titles per second according to BackType — even a boost from a superstar Twitter user like singer Katy Perry couldn’t do much to keep it alive, even though she has over 5 million followers (among other things, this raises the question of how active the millions of followers on celebrity accounts actually are).

One of the reasons for the short life-span could be that the tag just became so dominant that after awhile it was simply annoying — another thing media companies should be wary of (I logged off Twitter because my entire stream was #lessambitiousmovies). If you’re interested in more on what makes a good hashtag, Sloan had another recent post with some useful tips, including using other media to push the tag. And if you want to see trending hashtags, WhatTheTrend is a good place to do so.

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Post and thumbnail photo courtesy of Flickr user Steve Jurvetson