Be Specific

The more specific we make our personas, the more effective they are as design tools. That's because personas lose elasticity as they become specific. For example, we don't just say that Emilee uses business software. We say that Emilee uses WordPerfect version 5.1 to write letters to Gramma. We don't just let Emilee drive to work. We give her a dark-blue 1991 Toyota Camry, with a gray plastic kid's seat strapped into the back and an ugly scrape on the rear bumper. We don't just let Emilee go to work. We give her a job as a new-accounts clerk in a beige cubicle at Global Airways in Memphis, Tennessee. This distinctive specificity is very powerful as a design and communications tool. Consequently, all of our personas are articulated with singular detail and precision.

As we isolate Emilee with specific, idiosyncratic detail, a remarkable thing happens: She becomes a real person in the minds of the designers and programmers. We can refer to her by name, and she assumes a tangible solidity that puts all of our design assumptions in perspective. As she loses her elasticity, we can identify her skills, her motivations, and what she wants to achieve. Armed with this knowledge, we can then examine her in light of the software's subject area to see whether she is really an archetypal user. After a designer has some experience, he can usually synthesize a valid persona on the first try.

Giving the persona a name is one of the most important parts of successfully defining one. A persona without a name is simply not useful. Without a name, a persona will never be a concrete individual in anyone's mind.

All things being equal, I will use people of different races, genders, nationalities, and colors as personas. However, I try not to play against type because this can confuse everyone. Stereotypical personas are more effective if the stereotyping lends more credence to the persona. My goal here is not to be politically correct but to get everyone to believe that my personas are real. If my persona is a nurse, I will use a woman rather than a man, not because there are no male nurses, but because the overwhelming majority of nurses are female. If the user is a computer technician, our persona will be Nick, a pimply faced 23-year-old former member of the high-school audio-visual club, rather than Hellene, a statuesque, 5-foot-11-inch beauty who went to Beverly Hills High. I am shooting for believability, not diversity.

To make each persona more real to everyone involved in the product creation, I like to put faces to the names and give each persona an image. I usually purchase, for a small fee, faces from stock photo libraries on the Web. Occasionally, I've used sketched caricatures. You can cut them out of magazines if you want.

A fully realized, thoroughly defined user persona is a powerful tool. Until the user is precisely defined, the programmer can always imagine himself as the user or allow the user to become elastic. A completely defined user persona is key to the suppression of any tendency for the developer to usurp or distort the user persona's role. Long before a single line of code is written, a well-defined user persona becomes a remarkably effective tool for interaction design.