Who are your primary and secondary users?

Primary Users:

Random citizens

High school students on field trips

Objibwa Community College students

MTU Environmental Engineering students


Tourist visiting Lightfoot Bay

Amateur Scientist downloading the app from the web


Secondary Users:

High school teacher

Community College instructors

MTU Professor


MTU and NSF scientist

You should target your app design for the primary user, but also check the usability against the secondary users.

Perhaps you think that you know the MTU Environmental Engineering students. Do you really? But, you certainly do not know the high school students or the Objibwa Community College students.

Can give some attributes for the high school students?

Bully and tell other’s what to do

ADS, does not pay attention

Eager to learn

“Above it all” and does not want to comply


How tall are they? What are their ages? What are the technology experiences?

All the attributes can be contradictory. How can we express them?


They are hypothetical descriptions of specific potential users. They are a member of a class of user. They are not generalities rather they are specific characteristics. These give your potential users a face.

Website for personas:


Personas are said to be cognitively compelling because they put a personal human face on otherwise abstract data about customers. By thinking about the needs of a fictional persona, designers may be better able to infer what a real person might need. Such inference may assist with brainstorming, use case specification, and features definition. Pruitt and Adlin argue that personas are easy to communicate to engineering teams and thus allow engineers, developers, and others to absorb customer data in a palatable format. They present several examples of personas used for purposes of communication in various development projects.

Personas also help prevent some common design pitfalls which may otherwise be easy to fall into. The first is designing for what Cooper calls “The Elastic User” — by which he means that while making product decisions different stakeholders may define the ‘user’ according to their convenience. Defining personas helps the team have a shared understanding of the real users in terms of their goals, capabilities and contexts. Personas also help prevent “self referential design” when the designer or developer may unconsciously project their own mental models on the product design which may be very different from that of the target user population. Personas also provide a reality check by helping designers keep the focus of the design on cases that are most likely to be encountered for the target users and not on edge cases which usually won’t happen for the target population. According to Cooper, edge cases which should naturally be handled properly should not become the design focus.

The benefits are summarized as (Cooper, 1999):

  • Help team members share a specific, consistent understanding of various audience groups. Data about the groups can be put in a proper context and can be understood and remembered in coherent stories.
  • Proposed solutions can be guided by how well they meet the needs of individual user personas. Features can be prioritized based on how well they address the needs of one or more personas.
  • Provide a human “face” so as to focus empathy on the persons represented by the demographics.

Some pitfalls of personas:

  • Not one persona describes all the characteristics of the users
  • They cannot represent all the mix of characteristics
  • A persona is not a real user
  • Design may focus only their personas


Persona documentation can be lengthy. They typically include photos. (There are companies that provide pictures for personas.) They are given a name and a profession. Persona descriptions include a list of demographics information such as age, weight, height, etc. Personality characteristics and behaviors are described in a paragraph.

Example: Field Soldier Persona

Platoon A Private First Class

Private Jim Swayer

Age: 21

Height: 6′ 2″

Weight: 180 lbs

Right handed

Joe is an alert and strong. He generally follows orders but can also talk back to commanding officer. He does not shy away from a fight. He has above average intelligence.  He is skilled as a marksman. He was raised in the UP, so is fond of hunting. He is single and corresponds with his family infrequently.

Do you have a picture of Joe Swayar? Could you predict how he might perform using the Army App? Does he represent all soldiers?

Can we generate another persona, perhaps a soldier not so rash?

Company B Communication Specialist

Private Rod Smith

Age: 23

Height: 5′ 8″

Weight: 140 lbs

Left handed

Ron is an agile and fast. He has been enlisted for a couple of years. He is not sure if he will make a carrier in the Army. He follows orders and never argues with commanding officer. He avoids fights. . He is skilled as mechanic and can get equipment working.  He was raised on the east coast. He is single and corresponds frequently with family. He drinks infrequently and has several friends.

Is Rod different from Joe? Can you anticipate his use of the Army App? Is it different from Joe? Note after writing Rod’s persona, we get ideas of how to improve Joe’s persona.

Could we write a third persona?

These short personas are fun to write and do not take much time. In industry, the team may do market research to describe a more detail person. For example, designer of the Army App would interview many soldiers and commanders to get good description of personas.