Some Usability Terms

Card sorting - A technique to investigate how users tend to group items in order to maximize the possibility of their finding what they are looking for on the Web. The users are given a set of cards containing individual item names and are told to sort them into related piles and label the groups. Card sorting provides insight into the user’s mental model and suggests the structure and placement of items on a Web site.

Cognitive friction - A term relating to the relative difficulty of a task and the mental effort required to complete it. Tasks that present choices and actions in accordance to the user’s expectations are considered as having a low level of friction, while those that require deliberation are said to be high in cognitive friction.

Cognitive walkthrough - A usability testing strategy in which a developer group systematically evaluates each element on every screen in the context of the various tasks (e.g., how likely would a user click this button for Task A? What would happen if they did? Etc.).

Heuristics - Established principles of design and best practices in Web site design, used as a method of solving usability problems by using rules of thumb acquired from human factors experience.

Hierarchical drill-down - In Web site design, a type of structure where the user may jump from the home page to any number of pages and back to the home page again. (Also see Hub-and-spoke, Basic navigation structures.)

Hierarchical structures (in information architecture) - A set of various levels of groups and subgroups for categorizing items, often used to organize the content on a Web site.

High-level structure - The architectural structure of a Web site. Most easily seen with a diagram of the entire site, all its pages, and their inter-relationships.

Hooks - In journalism, a hook is a technique used to grab the reader’s attention. For example, a question: Would you like to lose ten pounds this week?

Hub-and-spoke - The study of the predispositions and constraints in human cognition, perceptual and motor systems in the context of interface development. That is, exploration of ways to develop safe and efficient technology and other artifacts such that they provide the best fit for human interaction. Traditionally the focus of Human Factors has been in engineering and industrial design systems such as aviation, military systems, manufacturing, and automotive design.

Information architecture - Part of the conceptual design stage; primarily associated with defining an organization for Web site content (but can include characterizing task flow or task relationships within a content organization). Includes the processes of defining site hierarchies, content organization, and labeling schemes for all types of menu systems, and the techniques for creating and evaluating them.

Interaction design - A term given to a set of design areas that focuses on the interaction value of content, as opposed to its presentation or information value. The interaction topics include Web controls, error handling, and feedback systems. The value of the term “interaction design” is relative; i.e., it is intended to differentiate these topics from other topics for purposes of evaluation and development.

Localization - The process of adapting a product to meet the linguistic, cultural, and other requirements of a specific target environment or market (or locale).

Personas - A concrete characterization of a single user group through a synthesis of the user, task, and environment profiles of that group. It provides detailed example of the potential end-user that represents a specific target audience type. Personas help developers think in terms of users by providing insight into how they might use the product. Especially helpful when there are no current users of the Web site.

Population stereotype - An established knowledge that a set of people have about the world, causing them to have strong expectations about how things should work, such as turning a knob or opening a door. People may thus be unpleasantly surprised if such expectations are not met with.

Phi phenomenon - A perceptual illusion in which a disembodied perception of motion is produced by a succession of still images, as described by Gestalt psychologist Max Wertheimer (1912) after experimenting with flashing lights in quick successions causing apparent movement.

Presentation design - A term given to a set of design areas that focuses on the presentation of information, as opposed to its information value. Presentation topics include layout, color management, graphics, and typography. The value of the term presentation design is relative; i.e., it is intended to differentiate these topics from other topics for purposes of evaluation and development.

Probes - The technique used in in-depth interviews to explore the interviewee’s emotions about the given topic. The questions asked gently nudge the interviewees to disclose their feelings. E.g., “How do you feel about shopping online?”

Progressive disclosure - An interaction design technique that provides information in sequence across a number of steps with increasing level of detail as requested by the user, to reduce information overload on the user.

Progressive image - Also known as interlaced image. Interlacing is a process by which the image is displayed in a series of passes, each skipping a certain number of lines, and the consecutive passes filling in the skipped lines. The image initially looks “fuzzy” and becomes clearer as the file loads, giving the viewer a blurry preview of the entire image rather than a clear incomplete picture. (Also see Interlaced image.)

Proximity - The Gestalt principle of grouping that states that items that are placed close together tend to be perceived as belonging together.

Reliability - In survey methodology, will a question elicit the same response over and over again? For example, “What is your shoe size?” is generally a reliable question. ”What is the date?” is not a reliable question.

Research and planning - The first stage of user-centered design, characterized by an evaluation of precursor designs and the gathering of business and user objectives for a new site. Typically includes setting business goals, defining user requirements, and understanding brand objectives.

Reverse card sort -  A usability testing technique, opposite to that of a card sort, where participants are given a list of items to see if they can figure out where to find them. Their success validates the self-evidence of the navigational structure of a design. (Also see Card sort.) Categories have already been made and labeled appropriately.

Satisficing - A theory of human problem solving that says people minimize expended effort by using shortcuts to make decisions. For instance, humans tend to select the first correct answer they encounter rather than rationally and systematically evaluating all possible answers prior to selection. This concept was first presented. by Herb Simon.

Scenario - 1. A concrete, often narrative description of a user performing a task in a specific context. Often a use scenario describes a desired or to-bebuilt function. This contrasts with a task scenario, which describes a currently implemented function.

2. A prescribed set of conditions under which a user will perform a set of tasks to achieve an objective defined by the developer.

Schema (pl. schemata) - A cluster of human memory that is described as a pattern of connections of neurons in the brain with nodes and links that are so strong that they can be retrieved together as a single memory unit. In essence, it is a packet of information based on knowledge and experience.

Signal / noise ratio - The proportion of meaningful content to extraneous interference. Writing is more powerful when the signal (message) is high and the noise (verbiage) is low. Maximize the signal/noise ratio.

Similarity - The Gestalt principle of grouping that states that items with the same size, shape, color or shade tend to be perceived as belonging together. (Also see Gestalt principles,Common region, Connectedness, Proximity.)

Stakeholder - Any individual who has vested interests in the design project and its outcome, including clients, managers, software developers, designers, marketers, distributors, store-owners, and almost everyone involved with the product.

SWAG - Scientific Wild Ass Guess, an estimation method.

Unique selling proposition (USP) - An exclusive message that concisely describes a product against its competition, and which the business or brand can use consistently in its advertising and promotion to achieve a cutting edge in the market.

Use case - A user-centered design method in which critical tasks are systematically documented with their prerequisites, the users’ steps and system steps, and the task outcome. Use cases are typically described in the abstract, which makes them particularly helpful in object-oriented design. Scenarios are concrete instantiations of use-cases.

Gestalt principles

A set of principles developed by the Gestalt Psychology Movement that established rules governing how humans perceive order in a complex field of objects. 

Gestalt principles of visual organization state that objects near each other, with same background, connected to each other, or having similar appearance are perceived as belonging to a group. (Also see Common region, Connectedness, Proximity, and Similarity.)

The Encyclopedia of Human-Computer Interaction, 2nd Ed