Usability engineering is a professional discipline that focuses on improving the usability of interactive systems. It draws on theories from computer science and psychology to define problems that occur during the use of such a system. Usability Engineering involves the testing of designs at various stages of the development process, with users or with usability experts. The history of usability engineering in this context dates back to the 1980s. In 1988, authors John Whiteside and John Bennett—of Digital Equipment Corporation and IBM, respectively—published material on the subject, isolating the early setting of goals, iterative evaluation, and prototyping as key activities. The usability expert Jakob Nielsen is a leader in the field of usability engineering. In his 1993 book Usability Engineering, Nielsen describes methods to use throughout a product development process—so designers can ensure they take into account the most important barriers to learnability, efficiency, memorability, error-free use, and subjective satisfaction before implementing the product. Nielsen’s work describes how to perform usability tests and how to use usability heuristics in the usability engineering lifecycle. Ensuring good usability via this process prevents problems in product adoption after release. Rather than focusing on finding solutions for usability problems—which is the focus of a UX or interaction designer—a usability engineer mainly concentrates on the research phase. In this sense, it is not strictly a design role, and many usability engineers have a background in computer science because of this. Despite this point, its connection to the design trade is absolutely crucial, not least as it delivers the framework by which designers can work so as to be sure that their products will connect properly with their target usership.
Usability can be described as the capacity of a system to provide a condition for its users to perform the tasks safely, effectively, and efficiently while enjoying the experience. In software engineering, usability is the degree to which a software can be used by specified consumers to achieve quantified objectives with effectiveness, efficiency, and satisfaction in a quantified context of use.
In software and systems engineering, the phrase use case is a polyseme with two senses:
- A usage scenario for a piece of software; often used in the plural to suggest situations where a piece of software may be useful.
- A potential scenario in which a system receives an external request and responds to it.
In systems engineering and software engineering, requirements analysis focuses on the tasks that determine the needs or conditions to meet the new or altered product or project, taking account of the possibly conflicting requirements of the various stakeholders, analyzing, documenting, validating, and managing software or system requirements.
The following outline is provided as an overview of and topical guide to human–computer interaction:
Human-centered computing (HCC) studies the design, development, and deployment of mixed-initiative human-computer systems. It is emerged from the convergence of multiple disciplines that are concerned both with understanding human beings and with the design of computational artifacts. Human-centered computing is closely related to human-computer interaction and information science. Human-centered computing is usually concerned with systems and practices of technology use while human-computer interaction is more focused on ergonomics and the usability of computing artifacts and information science is focused on practices surrounding the collection, manipulation, and use of information.
User interface (UI) design or user interface engineering is the design of user interfaces for machines and software, such as computers, home appliances, mobile devices, and other electronic devices, with the focus on maximizing usability and the user experience. In computer or software design, user interface (UI) design primarily focuses on information architecture. It is the process of building interfaces that clearly communicate to the user what's important. UI design refers to graphical user interfaces and other forms of interface design. The goal of user interface design is to make the user's interaction as simple and efficient as possible, in terms of accomplishing user goals. User-centered design is typically accomplished through the execution of modern design thinking which involves empathizing with the target audience, defining a problem statement, ideating potential solutions, prototyping wireframes, and testing prototypes in order to refine final interface mockups.
Ecological interface design (EID) is an approach to interface design that was introduced specifically for complex sociotechnical, real-time, and dynamic systems. It has been applied in a variety of domains including process control, aviation, and medicine.
A persona in user-centered design and marketing is a personalized fictional character created to represent a user type that might use a site, brand, or product in a similar way. Personas represent the similarities of consumer groups or segments. They are based on demographic and behavioural personal information collected from users, qualitative interviews, and participant observation. Personas are one of the outcomes of market segmentation, where marketers use the results of statistical analysis and qualitative observations to draw profiles, giving them names and personalities to paint a picture of a person that could exist in real life. The term persona is used widely in online and technology applications as well as in advertising, where other terms such as pen portraits may also be used.
Contextual inquiry (CI) is a user-centered design (UCD) research method, part of the contextual design methodology. A contextual inquiry interview is usually structured as an approximately two-hour, one-on-one interaction in which the researcher watches the user in the course of the user's normal activities and discusses those activities with the user.
User experience design, upon which is the centralized requirements for "User Experience Design Research", defines the experience a user would go through when interacting with a company, its services, and its products. User experience design is a user centered design approach because it considers the user's experience when using a product or platform. Research, data analysis, and test results drive design decisions in UX design rather than aesthetic preferences and opinions, for which is known as UX Design Research. Unlike user interface design, which focuses solely on the design of a computer interface, UX design encompasses all aspects of a user's perceived experience with a product or website, such as its usability, usefulness, desirability, brand perception, and overall performance. UX design is also an element of the customer experience (CX), and encompasses all design aspects and design stages that are around a customer's experience.
Contextual design (CD) is a user-centered design process developed by Hugh Beyer and Karen Holtzblatt. It incorporates ethnographic methods for gathering data relevant to the product via field studies, rationalizing workflows, and designing human–computer interfaces. In practice, this means that researchers aggregate data from customers in the field where people are living and applying these findings into a final product. Contextual design can be seen as an alternative to engineering and feature driven models of creating new systems.
Human-centered design is an approach to problem-solving commonly used in process, product, service and system design, management, and engineering frameworks that develops solutions to problems by involving the human perspective in all steps of the problem-solving process. Human involvement typically takes place in initially observing the problem within context, brainstorming, conceptualizing, developing concepts and implementing the solution.
Human-centered design is an approach to interactive systems development that aims to make systems usable and useful by focusing on the users, their needs and requirements, and by applying human factors/ergonomics, and usability knowledge and techniques. This approach enhances effectiveness and efficiency, improves human well-being, user satisfaction, accessibility and sustainability; and counteracts possible adverse effects of use on human health, safety and performance.
Human–computer interaction (HCI) is research in the design and the use of computer technology, which focuses on the interfaces between people (users) and computers. HCI researchers observe the ways humans interact with computers and design technologies that allow humans to interact with computers in novel ways. A device that allows interaction between human being and a computer is known as a "Human-computer Interface (HCI)".
Tools, devices or software must be evaluated before their release on the market from different points of view such as their technical properties or their usability. Usability evaluation allows assessing whether the product under evaluation is efficient enough, effective enough and sufficiently satisfactory for the users. For this assessment to be objective, there is a need for measurable goals that the system must achieve. That kind of goal is called a usability goal. They are objective criteria against which the results of the usability evaluation are compared to assess the usability of the product under evaluation.
Experience architecture (XA) is the art of articulating a clear user story/journey through an information architecture, interaction design and experience design that an end user navigates across products and services offered by the client or as intended by the designer. This visual representation is intended not only to highlight the systems that the end user will touch and interact with, but also the key interactions that the user will have with interacting the internal systems or back end structure of an application. It provides a holistic view of the experience, vertical knowledge of industry, the systems, documentation, and analysis of the points that should be focused on when delivering a holistic experience. The Experience architecture provides an overall direction for user experience actions across the projects.
Agile usability engineering is a method created from a combination of agile software development and usability engineering practices. Agile usability engineering attempts to apply the principles of rapid and iterative development to the field of user interface design.
User research focuses on understanding user behaviors, needs and motivations through interviews, surveys, usability evaluations and other forms of feedback methodologies. It is used to understand how people interact with products and evaluate whether design solutions meet their needs. This field of research aims at improving the user experience (UX) of products, services, or processes by incorporating experimental and observational research methods to guide the design, development, and refinement of a product. User research is used to improve a multitude of products like websites, mobile phones, medical devices, banking, government services and many more. It is an iterative process that can be used at anytime during product development and is a core part of user-centered design.
Behavioural design is a sub-category of design, which is concerned with how design can shape, or be used to influence human behaviour. All approaches of design for behaviour change acknowledge that artifacts have an important influence on human behaviour and/or behavioural decisions. They strongly draw on theories of behavioural change, including the division into personal, behavioural, and environmental characteristics as drivers for behaviour change. Areas in which design for behaviour change has been most commonly applied include health and wellbeing, sustainability, safety and social context, as well as crime prevention.
Elizabeth "Dori" Tunstall is a design anthropologist, researcher, academic leader, writer, and educator. She was dean of the faculty of design at OCAD University in Toronto, Canada, from 2016–2023, and the first black dean of a faculty of design anywhere. Tunstall holds a PhD and an MA in anthropology from Stanford University [1994–1999] and a BA in anthropology from Bryn Mawr College [1990–1994].
