Every now and again it’s interesting to find a case where the user interface design has resulted in completely different views of the same features. The usability-speak for this is that particular designs afford different uses. An open door, for instance, affords walking through it. A door handle affords pushing down and pulling. This is why putting handles on doors that are intended to be pushed is so confusing for people.

Essentially, Flickr tags and Gmail labels are pretty much the same thing. You can apply several of them to one thing, it helps you describe the thing (whether it be an email or a photo) and gives you an alternative way to browse your data.

There are some interesting differences of course too. Flickr tags are more about social organisation of data than Gmail labels — arguably, you’re the only one who’s going to need to find your email, whereas you want others to happen upon your photos. The most interesting difference, however, is a very simple interface design decision.

You assign Flickr tags to a photo by typing in the tags, separated by spaces. It is freeform — there’s no need to create the tag before you apply it, or to check spelling. There are downsides to this — if you forget how you’re classifying things, you might end up with duplicates. I’m pretty sure that I have multiple labels for the same thing — motorbike, bike, motorcycle, honda. Gmail labels, on the other hand, do need to be created first and are applied using a drop-down selector.

In terms of the interface design, the difference is small — a drop-down selection widget vs a freeform text box. Yet the effect on the use is very different. Flickr tags are a very new, if a little haphazard, way of organising your data. Gmail labels are just a slightly more advanced form of folders.

I think my point is that often people think of interface design as superficial, assuming that it’s just about how “nice” the application looks. Yet I’m sure there are many other cases where the presentation of the functionality has changed not only how users experience it but the reality of how they use a particular feature.

Have you guys got some examples to share?