User-centered design

Compare use-centered design and usage-centered design.

See also: Human-centered design

User-centered design (UCD) or user-driven development (UDD) is a framework of processes (not restricted to interfaces or technologies) in which usability goals, user characteristics, environment, tasks and workflow of a product, service or process are given extensive attention at each stage of the design process. These tests are conducted with or without actual users during each stage of the process from requirements, pre-production models and post production, completing a circle of proof back to and ensuring that "development proceeds with the user as the center of focus." Such testing is necessary as it is often very difficult for the designers of a product to understand intuitively the experiences of first-time users, and what each user's learning curve may look like. User-centered design is based on the understanding of a user, their demands, priorities and experiences and when used, is known to lead to an increased product usefulness and usability as it delivers satisfaction to the user. User-centered design applies cognitive science principles to create intuitive, efficient products by understanding users' mental processes, behaviors, and needs.

The chief difference from other product design philosophies is that user-centered design tries to optimize the product around how users can, want, or need to use it so that users are not forced to change their behavior and expectations to accommodate the product. The users thus stand in the center of two concentric circles. The inner circle includes the context of the product, the objectives of developing it, and the environment it would run in. The outer circle involves more granular details of task detail, task organization, and task flow.

History

The term "User-Centered Design" was coined by Rob Kling in 1977 and later adopted in Donald A. Norman's research laboratory at the University of California, San Diego. The concept became widely popular as a result of the publication of the book User-Centered System Design: New Perspectives on Human-Computer Interaction in 1986. The concept gained further attention and acceptance in Norman's seminal book The Design of Everyday Things (originally called The Psychology of Everyday Things). In this book, Norman describes the psychology behind what he deems 'good' and 'bad' design through examples. He exalts the importance of design in our everyday lives and the consequences of errors caused by bad designs.

The two books include principles for building well-designed products. His recommendations are based on the user's needs, leaving aside what he considers secondary issues like aesthetics. The main highlights of these are:

1. Simplifying the structure of the tasks such that the possible actions at any moment are intuitive.
2. Make things visible, including the conceptual model of the system, actions, results of actions and feedback.
3. Getting the mappings right between intended results and required actions.
4. Embracing and exploiting the constraints of systems.

In a later book, Emotional Design, Norman returns to some of his earlier ideas to elaborate what he had come to find as overly reductive.

Models and approaches

For example, the User-Centered Design process can help software designers fulfill the goal of a product engineered for their users. User requirements are considered right from the beginning and included in the whole product cycle. These requirements are noted and refined through investigative methods including: ethnographic study, contextual inquiry, prototype testing, usability testing and other methods. Generative methods may also be used including: card sorting, affinity diagramming and participatory design sessions. In addition, user requirements can be inferred by careful analysis of usable products similar to the product being designed.

User-Centered Design takes inspiration from the following models:

• Cooperative design: involving designers and users on an equal footing.This is the Scandinavian tradition of design of IT artifacts and it has been evolving since 1970. This is also called Co-design.
• Participatory design (PD), a North American term for the same concept, inspired by Cooperative Design, focuses on the participation of users. Since 1990, there has been a bi-annual Participatory Design Conference.
• Contextual design, "customer-centered design" in the actual context, including some ideas from Participatory design

Here are the principles that help in ensuring a design is user-centered:

1. Design is based upon an explicit understanding of users, tasks and environments.
2. Users are involved throughout design and development.
3. Design is driven and refined by user-centered evaluation.
4. Process is iterative.
5. Design addresses the whole user experience.
6. Design team includes multidisciplinary skills and perspectives.

User-centered design process

The goal of user-centered design is to make products that have very high usability. This includes how convenient the product is its usage, manageability, effectiveness, and how well the product is mapped to the user requirements. Below are the general phases of User-Centered Design process:

1. Specify context of use: Identify who the primary users of the product are, why they will use the product, what are their requirements and under what environment they will use it.
2. Specify requirements: Once the context is specified, it is time to identify the granular requirements of the product. This is an important phase which can further facilitate the designers to create storyboards, and set important goals to make the product successful.
3. Create design solutions and development: Based on product goals and requirements, start an iterative process of product design and development.
4. Evaluate product: Product designers do usability testing to get users' feedback for the product at every stage of User-Centered Design.

The above procedure is repeated in the next steps to finish the product further. These phases are general approaches and factors like design goals, team and their timeline, and environment in which the product is developed, determine the appropriate phases for a project and their order. You can either follow a waterfall model, agile model or any other software engineering practice.

Analysis tools

There are a number of tools that are used in the analysis of User-Centered Design, mainly: personas, scenarios, and essential use cases.

Persona

During the UCD process, a Persona representing the user may be created. A persona is a user archetype used to help guide decisions about product features, navigation, interactions, and even visual design. In most cases, personas are synthesized from a series of ethnographic interviews with real people, then captured in 1-2 page descriptions that include behavior patterns, goals, skills, attitudes, and environment, with a few fictional personal details to bring the persona to life.

See also

• Action research
• Activity-centered design
• Attentive user interface
• Chief experience officer (CXO)
• Component-based usability testing
• Contextual inquiry
• Design thinking
• Empathic design
• Extreme users
• Flexibility–usability tradeoff
• Human-centered computing
• Human-centered systems
• Human-centered design
• Information architecture
• Interaction design
• Meta-design
• Paper prototyping
• Participatory design
• Process-centered design
• Thanatosensitivity
• Transgenerational design
• Ubiquitous computing
• Usability
• World Usability Day

Further reading

• ISO 13407:1999 Human-centred design processes for interactive systems
• ISO 9241-210:2010 Ergonomics of human-system interaction -- Part 210: Human-centred design for interactive systems

Video

• Human Centered Design, IDEO’s David Kelley
• User Centered Design, Don Norman