Methods
Rapid Prototyping
Facts:
- Also called: Early prototyping, Low fidelity prototyping, Paper prototyping
- Lifecycle stages: Requirements, Design
The creation of low-cost representations of the user interface to a system as a method of brainstorming, creating, testing and communicating ideas about the system being developed.
- Basic Description
- How To
- Special Considerations
A prototype is a model of something to be further developed. The higher the fidelity the more representative is the prototype. Rapid prototyping implies that there is a short time between conceiving an initial notion and modeling it in physical form and between successive iterations. A popular method is to use paper to create the prototype (Snyder 2003) which can be done without programming skills and which has the look of work in progress thus encouraging users to comment on it. Software prototypes can then be developed when the ideas have been thought through and tested on paper. These can then be used for usability testing.
Outcomes and Deliverables
Representation of the system in a prototype form which has been in some way accepted by user representatives. (This will follow an iterative design process in which several prototypes have been produced.)
Benefits, Advantages and Disadvantages
Benefits
Rapid prototyping gives users (especially non-technical users such as the general public) a tangible demonstration of what the system is about. The use of pencil and paper and simple software development tools allows the prototype to be quickly replaced or changed in line with design feedback.
- Permits the swift development of interactive software prototypes.
- The prototypes created under this method support metric-based evaluations.
Advantages
- Allows design team to identify major navigation and usability problems before your company spends a lot of time and money developing and coding user interfaces.
- If the prototype is sufficiently well developed it can be used to support metric-based evaluations.
- The prototype can help to communicate the details of the user interface to the whole design team as well as to users. It can also be used as an awareness training tool with users.
Disadvantages
- Rushing in to develop a prototype may exclude other design ideas.
- Design features may be limited by the scope of the prototyping tool.
Cost-Effectiveness (ROI)
Experience shows that the method is very cost effective in highlighting the main problems with a product or system after a small number of iterations and user tests. More formal user tests of a software prototype which generate metrics (needed to ‘prove’ usability) will take more preparation and may require more detailed video analysis to generate the metrics which normally takes longer. It is not easy to measure ROI, as this rapid prototyping would typically be used early in the design process.
Read More About It
Originators/Popularizers
Low fidelity prototyping seems to have been advocated around 1990 by authors such as Jakob Nielsen, Bob Virzi and Tom Tullis. A few high-tech companies were using the technique during the 1980s as described by Robin Kinkead.
Authoritative References
Kavanaugh, R. and Soety, J. (2000) Prototyping using Visio, Usability Interface, 7(1).
Leone, P., Gillihan, D. and Rauch, T. (2000) Web-based prototyping for user sessions: Medium fidelity prototyping. Proceedings of the Society for Technical Communications 44th Annual Conference, pp231-234. Toronto, Canada: STC.
Nielsen, J. (1993) Usability engineering, Morgan Kaufman: Academic Press.
Contains a number of general references to prototyping as part of a general usability engineering process.
Rudd, J., Stern, K., and Isensee, S. (1996) Low vs. high-fidelity prototyping debate. Interactions, January: pp76-85.
Snyder, C. (2003) Paper prototyping, The fast and easy way to design and refine user interfaces, Elsevier Science.
A comprehensive source for understanding a simple but powerful technique.
Tullis, T.S. (1990) High-fidelity prototyping throughout the design process. Proceedings of the Human Factors and Ergonomics Society, 34th Annual Meeting, p266, Santa Monica, CA: HFES.
Uceta, F. A., Dixon, M. A. and Resnik, M. L., (1998) Adding interactivity to paper prototypes, Proceedings of the Human Factors and Ergonomics Society, 42nd Annual Meeting (Chicago), pp506-511. Santa Monica , CA: HFES.
Published Studies
See Snyder (2003) and Tullis (1990) for example case studies.
Related Subjects
- Paper prototyping: The user may be asked to interact with a paper prototype comprising a series of paper elements representing different parts of the interface and controlled by the evaluator or assistant. The user may point to interaction elements of the prototype or speak their inputs, which are then manipulated accordingly by the evaluator. The paper prototype provides enough detail to perform an evaluation relating to the function and flow of the interface, but not the look.
- Wizard of Oz: A user interacts with a computer system that is actually operated by a hidden developer - referred to as the 'wizard'. The wizard processes inputs from the user and responds with simulated system output. The approach is particularly suited to exploring design possibilities which are demanding to implement such as intelligent interfaces possibly featuring agents or advisors, and/or natural language processing.
- Video prototyping: Here a prototype is developed and it is videoed with an end user interacting with it. The video is then shown to end users to obtain feedback.
- Storyboard: A storyboard is a series of illustrations that represent a process, such as the steps of interacting with a computer or website. Storyboards can be used for checking that the steps of a process make sense to the user once the details are sketched.