jameshom.com | Usability Methods Toolbox | Low-Fidelity Prototyping

Low-Fidelity Prototyping

What is it?

Low-fidelity prototyping is a cheap way of providing prototypes to use in tests and participatory design sessions. "Low-fidelity" in this case means that the prototypes you use don't have to really look like the actual interface you're testing, as long as they "work" the same.

The idea is that you can get a lot of feedback about the interaction between the interface and the user by evaluating a low-fidelity prototype. Since low-fidelity prototypes are cheap, both in terms of money and time, you can afford to have more cycles of testing, more subjects, or more prototypes.

How do I do it?

Getting the prototype ready

The classic example of low-fidelity prototyping is using paper and pencil to mockup interface screens. These can be as simple as hand-drawn boxes with scribbled controls, or drawings done in a computer drawing program and printed out. Make one of each screen in the interface.

Also, make paper representations of menus, button groups, scroll bars, and the like. Post-It notes are good for this, as you can plunk them down on top of your "screen" as the user "clicks" on items, then rip them off as the state of the interface changes.

Some people use transparancies for layering elements on top of one another. I think that's too much trouble. Besides, one of the cool things about low-fidelity prototyping is that you can invent new interface elements during the evaluation session, simply by drawing them onto a Post-it note. Transparancies are a bit messier and harder to work with during the evaluation.

Low-Fidelity Prototyping in action

Now comes time to use the prototype in an evaluation session. For example, in an informal thinking-aloud protocol usability test, you could use two evaluators, one to run the test, and one to manipulate the prototype. Evaluator Two in essence pretends to be the computer--she reacts to the user's input by switching paper mockups around or placing or removing elements on the current mockup.

Sometimes the action can get pretty hectic, especially if you have one of those expert users that loves to click everywhere. It helps to have a number of elements pre-drawn, and organized (I've used a chessboard to sort small Post-it note elements in a matrix) so you can easily grab an element when you need it.

When should I use this technique?

Like any prototyping method, use this technique when you don't have the "real" interface yet; namely in earlier stages of development. This technique is great when you don't have a lot of money or time to spend on prototyping, and you're more concerned with user feedback than actual performance data.

Who can tell me more?

Click on any of the following links for more information:

Dumas, JS, and Redish, Janice, A Practical Guide to Usability Testing, 1993, Ablex, Norwood, NJ
ISBN 0-89391-991-8 (paper)

Nielsen, Jakob, "Paper versus Computer Implementations as Mockup Scenarios for Heuristic Evaluation'', Human-Computer Interaction-Interact `90, D. Diaper et. al. (ed.) Elsevier Science Publishers B.V. (North Holland), 1990: 315-320

Rettig, Marc, "Prototyping for Tiny Fingers (Everything I Need to Know About Prototyping, I Learned In Kindergarten)'', Communications of the ACM, April 1994.

Rubin, Jeffrey, Handbook of Usability Testing, 1994, John Wiley and Sons, New York, NY ISBN 0-471-59403-2 (paper)

Snyder, Carolyn, "Using Paper Prototypes to Manage Risk," October 1996, Software Design and Publisher Magazine

Virzi, Robert A, Sokolov, Jeff, and Karis, Demetrios. "Usability Problem Identification Using Both Low- and High-Fidelity Prototypes,'' 1995: Obtained directly from the authors.