Metaphorically Speaking...

I was just at the Nielsen Norman Group, Usability Week 2006 Conference, where I immersed myself in a 3-day Interaction Design bootcamp with Bruce "Tog" Tognazzini. An important point made by Tog was that metaphors are a good thing. Perhaps, that was more Martha Stewart-esq than he actually said it. Either way, this makes sense since metaphors are used as a teaching aid to enable people to recognize and make some sort of association with something else.

Recognizability is the goal. The right visual metaphor, sans words, can speak a thousand words but not if the metaphor is not easily recognizable. It can be the difference between 'huh' and 'aah' or slowing the user down and increased productivity. In many popular programs such as Paint or Photoshop, an image of a paint brush is used to denote painting, or a paint bucket for filling-in color, or an eraser for erasing, or a magnifying glass for enlarging, etc. There are no words alongside these icons, only alt text. Some metaphors, good or bad, have become learned and recognizable by users. As a result, they become the defacto standard and should be heeded closely when used. For example, Photoshop uses a capitalized "T" to denote the text type tool whereas, Paint uses an "A". They are similar enough and have become recognizable for what they represent. But, would a "B" or "Z" do the trick...probably not, given that "B" has become synonymous with bolding and "Z" is still universally TBD.

Visual metaphors can also be just the fix in a real estate crunch. However, if there is no space for accompanying text, other than the obligatory alt text, its even more important that users be able to instantly recognize what the icon represents. Additionally, such metaphors can also serve to add some visual interest to a page and call more attention to the function it metaphorically represents.