Paper prototyping

Paper prototyping is a widely used method in the user-centered design process, a process that helps developers to create software that meets the user's expectations and needs— in this case, especially for designing and testing user interfaces. It is throwaway prototyping and involves creating rough, even hand sketched, drawings of an interface to use as prototypes, or models, of a design.

History

Paper prototyping started in the mid 1980s and then became popular in the mid 1990s when companies such as IBM, Honeywell, Microsoft, and others started using the technique in developing their products.

Benefits

Paper prototyping saves time and money since it enables developers to test product interfaces (from software and websites to cell phones and microwave ovens) before they write code or begin development. This also allows for easy and inexpensive modification to existing designs. Iterative usability testing of prototypes leads designers and developers to a progressively bug-free interface, which they can then develop with a fair amount of confidence.

There are different methods of paper prototyping, each of them showing several benefits regarding the communication within the development team and the quality of the product to be developed: In the development team paper prototypes can serve as a visual specification of the graphical user interface, and by this means assure the quality of a software. Prototyping forces a more complete design of the user interface to be captured. In team meetings they provide a communication base between the team members. Testing prototypes at an early stage in development helps to identify software usability problems even before any code is written. The costs and annoyances of later changes are reduced, the support burden is lowered, and the overall quality of the software or website is increased.

Creating paper prototypes

Parts to implement

Paper prototypes usually cannot mirror the whole software or web site to be produced. It is necessary to limit the scope of the prototype by focus or width and depth. Limiting a prototype by focus means to either show the uncertain and difficult issues or the well-known and easily designed ones. Width and depth refer to the level of generality of the prototype: Should the prototype represent the whole design without providing any detailed function, or should certain issues be shown in detail?

It is useful to concentrate on the general design rather than details, in early stages of the conceptual phase, to probe if the overall design meets the user's expectations. Specific details may be tested isolated from the general design later in the conceptual or implementation phases.

How to create paper prototypes

The individual interface elements of a paper prototype are painted or printed on paper, cut out, and put onto another piece of paper which models the computer screen. The arrangement of the interface elements can then be changed quickly and without programming, labels can be renamed, and objects added, removed, or replaced by other input widgets. The sequence of dialogs or pages in a web site can be varied on the fly, which makes it easy to test multiple versions of an application's Interaction design.

Applying paper prototypes

The most important areas of application of paper prototypes are the following:

;Communication in the Team:One of the major applications of Paper Prototyping is brainstorming in the development team, to collect and visualise ideas on how an interface might look. The interface is built up step by step, meeting the expectations of all team members. To probe the applicability of the software design, typical use cases are played through and possible pitfalls are identified. The prototype can then be used as a visual specification of the software.

;Usability Testing:Paper prototypes can be used for usability testing with five to ten real users. In such a test, the user performs realistic tasks by interacting with the paper prototype. The prototype is manipulated by another person reflecting the software's reactions to the user input actions. Though seemingly unsophisticated, this method is very successful at discovering usability issues early in the design process.

;Design Testing:Especially in Web Design, paper prototypes can be used to probe the illegibility of a design: A high-fidelity design mockup of a page is printed and presented to a user. Among other relevant issues the user is asked to identify the main navigation, clickable elements, etc. Paper prototyping is also the recommended design testing technique in the contextual design process.

;Information Architecture:By applying general and wide paper prototypes, the information architecture of a software or web site can be tested. Users are asked where they would search for certain functionality or settings in software, or topics in a web site. According to the percentage of correct answers, the information architecture can be approved or further refined.

See also

* Prototyping
* Software Prototyping
* User Centered Design

External links

* [http://www.nngroup.com/reports/prototyping/video_stills.html 7 photos] of paper prototyping
* [http://www.alistapart.com/articles/paperprototyping Paper Prototyping Article]