Size Matters: Tag Clouds & Metadata Literacy

David Warlick is on to something (again? still?): the potential of word or tag clouds. You know these things: a group of words in different font sizes (and/or colours & font styles) are presented together in a cluster, with the larger words representing something more popular than the smaller words.

Many sites deliver their information content in this way, or allow you to represent your own content this way; respective examples include Digg's Bigspy and Wordle. There are many, many others, and popular social networking systems (see Twittersheep) are starting to adopt them, too.

I think there's a reason for their popularity: they distill a potentially useful kind of meaning from a lot of content, and deliver that meaning in a concise, visual way. Aside from just being cool, these clouds are a way of instantly, visually giving information about information: interpreting them requires a kind of new "metadata literacy": the font size adds a new layer of "reading" to text. You could argue that things like larger titles in textbooks or headlines in newspapers have always done this, and you'd be correct. But remember also that we learn to interpret size in these contexts through our education systems: who doesn't remember the "Newspaper Unit" from their schooldays?

In the Web 2.0 world, maybe, amongst other things, we need to teach this relatively new context of font size meaning something other than "title." If font size now means "popularity" too, then perhaps we need to facilitate contextual interpretation of information (how's that for a definition of teaching?). Maybe students could tell us what it means to them, too...

One other great thing about clouds is that they use text to tap into the competencies of visual learners: you can see the importance of a word in a word cloud. This, as Warlick suggests, may have useful applications in education, his example being "one way of reading the chapter of a text book might be to view and explore its tag cloud." I like it.