Specialization of design focused on the experience users have of a product or service
Interaction design, often abbreviated as IxD, is "the practice of designing interactive digital products, environments, systems, and services.": xxvii, 30 Beyond the digital aspect, interaction design is also useful when creating physical (non-digital) products, exploring how a user might interact with it. Common topics of interaction design include design, human–computer interaction, and software development. While interaction design has an interest in form (similar to other design fields), its main area of focus rests on behavior.: xxvii, 30 Rather than analyzing how things are, interaction design synthesizes and imagines things as they could be. This element of interaction design is what characterizes IxD as a design field as opposed to a science or engineering field.
While disciplines such as software engineering have a heavy focus on designing for technical stakeholders, interaction design is focused on meeting the needs and optimizing the experience of users, within relevant technical or business constraints.: xviii
The term interaction design was coined by Bill Moggridge and Bill Verplank in the mid-1980s, but it took 10 years before the concept started to take hold.: 31 To Verplank, it was an adaptation of the computer science term user interface design for the industrial design profession. To Moggridge, it was an improvement over soft-face, which he had coined in 1984 to refer to the application of industrial design to products containing software.
The first academic program officially named "Interaction Design" was established at Carnegie Mellon University in 1994 as a Master of Design in Interaction Design. At the outset, the program focused mainly on screen interfaces, before shifting to a greater emphasis on the "big picture" aspects of interaction—people, organizations, culture, service and system.
Goal-oriented design (or Goal-Directed design) "is concerned with satisfying the needs and desires of the users of a product or service.": xxviii, 31
Alan Cooper argues in The Inmates Are Running the Asylum that we need a new approach to solving interactive software-based problems.: 1 The problems with designing computer interfaces are fundamentally different from those that do not include software (e.g., hammers). Cooper introduces the concept of cognitive friction, which is when the interface of a design is complex and difficult to use, and behaves inconsistently and unexpectedly, possessing different modes.: 22
Alternatively, interfaces can be designed to serve the needs of the service/product provider. User needs may be poorly served by this approach.
Usability answers the question "can someone use this interface?". Jakob Nielsen describes usability as the quality attribute that describes how usable the interface is. Shneiderman proposes principles for designing more usable interfaces called "Eight Golden Rules of Interface Design"—which are well-known heuristics for creating usable systems.
Personas are archetypes that describe the various goals and observed behaviour patterns among users.
A persona encapsulates critical behavioural data in a way that both designers and stakeholders can understand, remember, and relate to. Personas use storytelling to engage users' social and emotional aspects, which helps designers to either visualize the best product behaviour or see why the recommended design is successful.
The cognitive dimensions framework provides a vocabulary to evaluate and modify design solutions. Cognitive dimensions offer a lightweight approach to analysis of a design quality, rather than an in-depth, detailed description. They provide a common vocabulary for discussing notation, user interface or programming language design.
Dimensions provide high-level descriptions of the interface and how the user interacts with it: examples include consistency, error-proneness, hard mental operations, viscosity and premature commitment. These concepts aid the creation of new designs from existing ones through design maneuvers that alter the design within a particular dimension.
Designers must be aware of elements that influence user emotional responses. For instance, products must convey positive emotions while avoiding negative ones. Other important aspects include motivational, learning, creative, social and persuasive influences. One method that can help convey such aspects is for example, the use of dynamic icons, animations and sound to help communicate, creating a sense of interactivity. Interface aspects such as fonts, color palettes and graphical layouts can influence acceptance. Studies showed that affective aspects can affect perceptions of usability.
Emotion and pleasure theories exist to explain interface responses. These include Don Norman's emotional design model, Patrick Jordan's pleasure model and McCarthy and Wright's Technology as Experience framework.
The concept of dimensions of interaction design were introduced in Moggridge's book Designing Interactions. Crampton Smith wrote that interaction design draws on four existing design languages, 1D, 2D, 3D, 4D. Silver later proposed a fifth dimension, behaviour.
The Interaction Design Association was created in 2003 to serve the community. The organization has over 80,000 members and more than 173 local groups. IxDA hosts Interaction the annual interaction design conference, and the Interaction Awards.
The core principles of industrial design overlap with those of interaction design. Industrial designers use their knowledge of physical form, color, aesthetics, human perception and desire, and usability to create a fit of an object with the person using it.
Academic research in human–computer interaction (HCI) includes methods for describing and testing the usability of interacting with an interface, such as cognitive dimensions and the cognitive walkthrough.
Interaction designers are typically informed through iterative cycles of user research. User research is used to identify the needs, motivations and behaviors of end users. They design with an emphasis on user goals and experience, and evaluate designs in terms of usability and affective influence.
Like user interface design and experience design, interaction design is often associated with the design of system interfaces in a variety of media but concentrates on the aspects of the interface that define and present its behavior over time, with a focus on developing the system to respond to the user's experience and not the other way around.
Tinauli, Musstanser; Pillan, Margherita (2008). "Interaction Design and Experiential Factors: A Novel Case Study on Digital Pen and Paper". Mobility '08: Proceedings of the International Conference on Mobile Technology, Applications, and Systems. New York: ACM. doi:10.1145/1506270.1506400. ISBN978-1-60558-089-0.