Glossary

7 plus or minus 2: The number of items that can be held in short-term memory or that can be the focus of attention, as stated by George A. Miller in his 1956 paper. The number applies only to retention and recall of information, and not to recognition. “The Magic Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information” (The Psychological Review, 1956, vol. 63, pp. 81-97). SEE HICK’S LAW AND CHUNKING

Accessibility: The attributes and characteristics of a system that allow people with limited vision, hearing, dexterity, cognition or physical mobility to interact effectively with the system. Standards and guidelines are available, and standards may be legally enforced in some markets. Accessibility aids, such as screen readers, may be added to a system to allow people with disabilities to use those systems.

Affordance: The properties of an object that inform people how the object could be used. The term "perceived affordance" applies when the object properties are perceived in a way that differs from the real-world, physical properties, especially when the usage of the object depends on perceived rather than real-world properties.

Brainstorming: A method for generating ideas, intended to inspire the free-flowing sharing of thoughts of an individual or a group of people, typically while withholding criticism in order to promote uninhibited thinking. See also metaphor brainstorming.

Card Sorting: A method for organizing information that involves sorting a series of cards into groups that make sense to the participants. Each card represents a single term, function or object. Card sorting helps to reveal users' mental models, or patterns that the end users would expect to find. Read more about card sorting.

Case Study: A way of learning about a complex instance through extensive description and analysis. The case study articulates why the instance occurred as it did by exploring the factors contributing to its success or failure, and what one might consider in similar situations.

Chunking: The human ability to group information into related small sets, which can then be stored in short-term memory. By keeping information in smaller pieces, the functional storage capacity of the brain is increased. Information is often presented in a chunked format to facilitate human memory, for example North American phone numbers are often grouped into the xxx-xxx-xxxx pattern. Familiarly with the information and/or rehearsal of it increases the person’s ability to remember the information.

Conspicuity: The characteristics of a graphic element that enable the audience to differentiate the element from its surrounding environment. Conspicuity is achieved when each element can easily be distinguished separately by the user.

Contextual Inquiry

A semi-structured field interviewing method based on a set of principles that allow it to be molded to different situations. This technique is generally used at the beginning of the design process and is good for getting rich information, but can be complex and time consuming. The four principles are:

Focus - plan for the inquiry based on a clear understanding of your purpose
Context - go to the customers' workplace and watch them do their own work
Partnership - talk to customers about their work and engage them in uncovering unarticulated aspects of work
Interpretation - develop a shared understanding with the customer about the aspects of work that matter

Parts from Contextual Design (Hugh Beyer and Karen Holtzblatt). Read more about Contextual Inquiry.

Culture: The shared set of habits, customs, knowledge, beliefs, language, and behaviors that set one group of people apart from others. This grouping may range from very large to very small groups (such as an office or a business). Culture is invisible to people who are part of it, and often incomprehensible to people who are encountering a specific culture for the first time. The risk of culture for usability is that culture is a deep source of unstated assumptions. These assumptions need to be identified and stated explicitly before they can be incorporated into a usable design.

Easy to Learn: The aspect of usability that focuses on facilitating the users learning of an interface, with minimum time and effort spent in the learning phase.

Effective: The attribute of usability that focuses on task completion, guiding the user through all parts of the task and ensuring that the task is properly completed.

Efficiency: The attribute of usability that focuses on being able to accomplish a task in minimum time with a minimum of effort.

Engaging: The aspect of usability that focuses on capturing and holding the user's attention and interest.

Ethnography: The process of gathering information about users and tasks directly from users in their normal work, home or leisure environment. Traditional ethnography focuses on long-term studies spanning weeks, months, or even years. Information may be collected through observation, interviews, audio or video recording, observer logs, artifact collection, diaries and photographs. Ethnography is a valuable source of data for creating personas, scenarios, and storyboard. Read more about ethnography.

Facilitator: A person that works with a person or group to lead a discussion or activity in order to extract feedback and information. A facilitator's goals might include developing an understanding of a situation or objective, help achieve consensus, understand the differences or obstacles that stand in the way of the end goals, and clarify various view points. Key skills for a facilitator include timekeeping, application of behavioral tools to help achieve the desired test or activity goals, listening, asking questions, suggesting alternatives, and moving the test or activity forward and keeping records. A facilitator might preside over various forms of user research. SEE MODERATOR

Fishbone Diagram

A graphic that is created to identify cause-and-effect relationships among factors in a given situation. It is made up of a "head" which states a problem and bones along the spine which represent factors and categories of factors. Alternative names for this technique are: cause-and-effect diagram or root cause analysis.

The Ishikawa Diagram, developed by Kaoru Ishikawa for industrial quality control, was the first graphic to focus on identifying the causes of an undesired effect.

A related technique developed by NASA is called a Fault tree diagram and uses a box and arrow format to display the various possible scenarios for a given event.

Fitts' Law: The further away a target is, and the smaller its size, the longer it will take for a user to reach it. The time required to move from a starting point to within the confines of a target area is dependent on a logarithmic relationship between the distance from the point to the target area and the size of the target.

Formative Evaluation: Formative evaluation is a type of usability evaluation that helps to "form" the design for a product or service. Formative evaluations involve evaluating a product or service during development, often iteratively, with the goal of detecting and eliminating usability problems. Read more about formative evaluation.

Gestalt Principles

Humans visually perceive items not in isolation, but as part of a larger whole. These principles include humans tendencies towards:

Similarity - grouping items by their analogous characteristics
Proximity - grouping items by their physical closeness to each other
Continuity - grouping items together when there is an identifiable pattern
Closure - completing or filling in missing features

Graceful Degradation: Systems should be designed so that when features that take advantage of new technologies are disabled, the content maintains effectiveness for the users. For example, older Web browsers and browsers which allow users to disable features will display page content in a simplified format.

Heuristic: A usability guideline for evaluating a user interface, which can be used to identify design problems. Usability heuristics often need to be adjusted depending on the interface and the technology used. There are lists of heuristics that have been compiled by various people and organizations that are commonly used for this method. Read more about heuristic evaluation.

Hick's law (Hick-Hyman law): The time it takes to make a decision increases proportionally to the number and complexity of choices. Hick’s law is the appropriate model in choosing an alternative from a menu or navigation bar for decision times, rather than Miller’s “magic number” of seven plus or minus two.

Human Factors: The multidisciplinary study of human biological, physical, psychological, and social characteristics in relation to environments, objects and services. The practice of human factors applies to the design, operation, and evaluation of systems to ensure that that they are safe, efficient, comfortable and aesthetically pleasing to humans.

Human-Computer Interaction (HCI): A discipline concerned with the design,evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them. (HCI Bibliography, http://sigchi.org/cdg/cdg2.html#2_1)

Industrial Design: An applied art focusing on the aesthetics, usability, ergonomics, and production of physical products, such as automobiles, appliances and consumer electronics. Industrial designers may specify the overall shape, interactive properties, colors, texture, and sounds of an object, as well aspects of the manufacturing process.

Information Architecture (IA): The process of organizing information including the structure, design, layout and navigation in a way that is easy for people to find, understand and manage the information.

Interaction Design (ID): The creation of behavior and communication tools and processes that facilitate communication between humans and objects, services, and physical or virtual environments, and that allow manipulation of those objects, services, and environments. It is important to study the flow of information and the discourse between the human and the interface including feedback and stimulus-response over a period of time.

Interface: A view or presentation of an object, service, or environment that a person (or group) interacts with, and the capabilities that provide for interaction across the interface.

Internationalization: The process of developing a system whose core design works in multiple languages and in the cultural contexts of different locales, without having to be redesigned for each locale.See localization. Read more about internationalization.

Iterative Design: Design methodology involving repeated cycles of design, evaluation, and analysis. Refinements are made for the next cycle based on the analysis and feedback. SEE USER-CENTERED DESIGN

Learnability: A measure of the degree to which a user interface can be learned; an attribute of a usable system. The ease of learning the functionality of a system and gaining proficiency to complete basic and necessary tasks. Factors affecting this measure include the amount of time, training, and support required for the user to learn the system. SEE READABILILTY AND USABILITY

Likert Scale: A response range for a type of survey question in which a person is asked to agree or disagree with a statement. The scale typically runs from 1 ("strongly disagree") to 5 or 7 ("strongly agree"). With a Likert scale, neither the numerical scores nor the intervals between score values have any intrinsic meaning. See also rating scales.

Localization: Customizing an internationalized product for a specific market. When a product has been properly internationalized, the visual design can be preserved when it is adapted for a particular audience, even while the language is translated, formats converted and layout adjusted. See internationalization.

Metaphor Brainstorming: Metaphor brainstorming is a method for generating metaphors and extracting aspects of those metaphors that can be applied to the design of hardware, software, processes, and services. SEE Brainstorming. Read more about Metaphor Brainstorming.

Moderator: A person that works with a group to regulate, but not lead, a discussion. Whereas a facilitator might take charge of a discussion to shepherd it in a specific direction, a moderator remains passive, without explicitly leading the process or driving a desired outcome. A moderator takes the lead from the participants, listening and intervening only when necessary to encourage further discussion or ask for clarity for other participants or audiences. SEE FACILITATOR

Persona: Fictional person created to model and describe the goals, needs, and characteristics of a specific type or group of users. Does not describe a real, individual user nor an average user. Often includes made-up personal details to make the fictional person more "real".

Prototype: An experimental design of the whole or part of a product used for illustration or testing purposes.
[http://www.theusabilitycompany.com/resources/glossary/prototype.html] SEE WIREFRAME

Readability: A measure of the degree to which an interface can be easily and accurately read; an attribute of a usable system. The level of difficulty of vocabulary and the complexity of sentences in a written text usually ranked by the age or grade level required for a person to readily understand the text. People can more easily perceive a message correctly when the vocabulary and sentences are simple and clear. SEE LEARNABILITY AND USABILITY

Scenario: A story which has the key elements of a realistic situation when the user would interact with the system being designed or evaluated. The scenario includes consideration of the user's goals, tasks and interaction. Scenarios can be created for user groups, workflows or tasks to explore, understand and test the different types of needs and goals.

Site Map: A representation of the information that can be found on a Website or of a system. When presented as content on a Website it is typically organized in a hierarchical listing. Alternatively, the same information can be represented with boxes and arrows that visually show the hierarchy of the interface.

Storyboard: A technique for illustrating an interaction between a person and a product (or multiple people and multiple products) in narrative format, which includes a series of drawings, sketches, or pictures and sometimes words that tell a story. Read more about storyboard method.

Task: The procedures that include goals, steps, skills, start state, inputs, end state, and outputs required to accomplish an activity. They can be organized into larger tasks such as driving to work and sub-tasks such as opening the car door.

Taxonomy: A scheme for classifying a body of knowledge and defining the relationships among the pieces. Sometimes referred to as a controlled vocabulary, a taxonomy is often used to classify content to aid in the creation of information architecture. SEE INFORMATION ARCHITECTURE

Testing (usability): The process of validating that a system meets pre-specified usability objectives. These objectives should be task-based, and should tie directly to product requirements, including results from analytic tools such as personas, scenarios, and task analysis. Testing may validate a number of objective and subjective characteristics, including task completion, time on task, error rates, and user satisfaction. Testing may be formal or informal, may be local (with testers physically present at same location as users) or remote, and may result in qualitative or quantitative data. Testing may occur at any point in the development cycle, from early analysis through product delivery and beyond. Testing may be based on paper designs, models, or display mock-ups, as well as on products in development and completed products.

Think-aloud protocol: A direct observation method of user testing that involves asking users to think out loud as they are performing a task. Users are asked to say whatever they are looking at, thinking, doing, and feeling at each moment. This method is especially helpful for determining users' expectations and identifying what aspects of a system are confusing.

Usability: A measure of the degree to which a product can be used by specified users or groups to achieve specific goals of effectiveness, efficiency, and satisfaction in a specified context of use. Factors affecting this measure include learnability, readability, aesthetics, safety and error frequency. Another significant factor is keeping cost-effectiveness within acceptable levels for human cost measured in terms of tiredness, discomfort, embarrassment, frustration and personal effort. Keeping cost-effectiveness within acceptable levels increases user satisfaction, which in turn causes continued and enhanced usage of the system. SEE LEARNABILITY, READABILITY AND TESTING

Usability Engineering (Human Factors Engineer): The disciplined application of usability practices to assess the needs and abilities of users, in conjunction with the business requirements, practices, and processes of an organization. These are combined to develop an effective user experience, and to integrate that experience into a product or service. Usability engineering also encompasses the business and interpersonal skills to work effectively with the business and development organizations to integrate usability practices and goals within the overall development, marketing, support, training, and quality assurance processes of the product group.

User Experience (UE): Every aspect of the user's interaction with a product, service, or company that make up the user's perceptions of the whole. User experience design as a discipline is concerned with all the elements that together make up that interface, including layout, visual design, text, brand, sound, and interaction. UE works to coordinate these elements to allow for the best possible interaction by users.

User-Centered Design (UCD): An approach or philosophy that emphasizes early and continuous involvement of users in the design and evaluation process.

Wayfinding: How people orient themselves and navigate in a built environment, both physical and virtual.

Wireframe: Rough outline of navigation and content elements that make up a user interface. Typically visual design and precise layout are not addressed. SEE PROTOTYPE

Wizard of Oz: A user-based evaluation of unimplemented technology where, generally unknown to the user, a human or team is simulating some or all the responses of the system. Read more about Wizard of Oz.

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