What is "Tag Cloud"?

What to hell are tag clouds or popular tags? In 2002 Jim Flanagan was the first using tag clouds as a display form. Flickr, Technorati and Blogs have tightened the trend in the design business and today leading enterprises like Spiegel.de, O2-online and others use this tool. Will tag clouds become a trend , like a lot of before which came and disappeared again when we recognized that we benefit less than we thought from them ? A tag cloud is a mean of visualisation of information within a specified area.

Looking the first time at a tag cloud you will think that the designer has freely chosen the arrangement of the words. However this is not the fact, the single catchwords are arranged to each other and stressed graphically according to their importance using for example bold type or a larger font size. Studies showed that the presentation of catchwords in a tag cloud is better remembered by the observer than a simple word list of these 100 words.

However it was also pointed out that only 6 out of 100 words from the tag cloud were memorized very well and these were the words which have been stressed. So if you use tag clouds pay attention that you do not overload them, doing so you will experience the same negative side effect as using a overloaded sitemap. The viewer will lose the overview and the mind for a closer deal with the source. The importance of a word in tag cloud depends on its frequency of use, however the arrangement of the word is performed alphabetically. This enables you to look for a word alphabetically or due to the frequency of use. Some designer prefer to cluster the tags semantically so that similar tags will appear near each other.

Often the single words of the tag clouds are links and can be selected to receive more information on the item. There are three main/basic types of tag clouds. In the first type the size stands for the number of times that the tag has been applied to a single item. This remindes a little bit of a democratical election.

The second type is the most commonly used type. Here the size represents the number of items to which a tag has been applied, as a presentation of each tag's popularity. In the third type, tags are used as a categorization method for content items. Tags are represented in a cloud where larger tags represent the quantity of content items in that category.

Opinions differ concerning the sense and senselessness of the tag clouds. The advantages are that tag clouds have a very simple design, are easy to understand and by their stil don't suffer from the labeling problems of bar charts, bubble charts , treemaps etc. A little bit disadvantageous is the fact that longer words are stressed more than shorter words.

An other problem with tag clouds is that words whose letters contain many ascenders and descenders may receive undue attention as well. Depended on the type of words used the tag cloud can become less efficient. However the art is to combine the mentioned advantages and disadvantage together using the tag cloud as tool on the way to an efficient visualisation.