Last time I talked about how the hash tag can make you a more elegant copywriter and help you create a context for your Social Media content without wasting unnecessary space from the limited 140 characters.

However, there are many other uses of hash tags. In fact, this is not an official Twitter shortcut such as the @, which directs the tweet at the user you place immediately after the symbol. No, it has been introduced by the users themselves and therefore merely relies on a code of conduct and general consensus. But since it is the users we care about, and not twitter, that's actually quite important.

Once you understand your audience and who you're talking to, coining a hash tag to promote a Social Media campaign is only one step away.

Hash tags tend to shift a little here and there in the beginning of their existence. Make sure you're the first to create yours or understand which ones are trending in order to plug into the already established hash tag. At the beginning they may look like #health2eu, #HealthForTheEUParis, #HealthConferenceParisEU2 etc. The variations are of course endless. The shortest version, however, often tends to win the upper hand and more often than not, very quickly establishes itself. In the case of the Health 2.0 Europe conference in Paris, the trending hash tag turned out to be #health2eu.

Topic or Event

This is used to a great extent for conferences but is also usually the type of hash tag which holds the majority of positions in the top trending topics. There are some famous recurring trending hash tags such as #NowPlaying and #ff (Follow Friday, I'll be discussing this in another article), which is used across the different cliques and ages of twitter. Much like the 'voice' of a group, each has their own recurring hash tag themes and topics. For example, in my own group I see a lot of #TodayIAmWearing, a hash tag and campaign coined by UK Vogue.

Event hash tags almost deserve their own category for being such a popular use of hash tags that it even prompted some useful tools to emerge. In many cases, the hash tag for a conference starts with the official announcement, for example #health2eu and start of the discussion. This can range from excited chatter to logistics questions to already full on discussions. Events tags are one of the few hash tags that are easily and very quickly established with a majority of consensus. To get the most out of a conference hash tag, use some of the following tools, which allow you to respond, chat and update as well as follow:

* http://tweetchat.com/ This is an extremely useful application which gives you three options to choose from and facilitates the use of hash tags tenfold
* http://tweetgrid.com/ Useful for when hash tags are not quite agreed upon yet - you can create a grid with a window for each variation of the hash tag allowing to follow them all at once.

Rules

* Keep it short
* Tweets are real time feeds - dates aren't necessary. Not #WorkMeet2010 - #WorkMeet will do and means it can be used again later
* Use uppercase letters for each new word
* Don't use spaces or symbols such as '& etc, it will break the tag
* Use proper grammar. Not #YoureCool but #YouAreCool since #You'reCool will look like #You

Handy #Tools

If you're using the actual twitter page, you can see trending topics on your homepage on the right side. However, sometimes it is advisable to use some helpful tools

* http://hashtags.org/ Where you can see the trends neatly displayed in a graph as well as an even neater layout listing the users, actual tweet and time
* http://www.whatthetrend.com/ This is a great place to understand what those trending topics on the right actually mean or stand for - a useful tool when you'd like to join in but don't understand what the deal is 100%. You want to know before you engage!
* http://twubs.com/ Particularly useful to find grouped trending tags ranging from conferences to news to TV

Go ahead, try it! But don't forget to actually engage within the content of the rest of the tweet, otherwise the hash tag is just a lonely signpost.