Usability
Glossary |
PhD Work>Usability Glossary
These Usability terms are based on a book by Jenny Preece titled "A Guide to Usability: Human Factors in Computing". These terms are definitely useful for HCI beginners, especially.
There are currently 110 terms in Usability Glossary.
| Term | Meaning |
| Affordance | An aspect of an object which makes it obvious how the object is to be used; for example, a panel on a door to indicate 'push' and a vertical handle to indicate 'pull'. |
| Agent | A character that initiates action. |
| Analytic evaluation | A type of evaluation that uses formal or semi-formal interface description to predict user performance. |
| Anthropology | The study of the physical and cultural aspects of humankind. |
| Artificial Intelligence (AI) | The study of how computers can mimic human thought and the insights this can give about how people think. |
| Auditory output device | An output device that uses sound. |
| Backus-Naur Form (BNF) | A grammatical notation used to specify programming languages. |
| Benchmark task | A standard laboratory task used by many companies in the evaluation of products. |
| Bespoke system | A system commissioned by an organisation for its own use. |
| CD-ROM | (Compact disk-read only memory)an adaptation of optical read-only compact disks for use with general digital data. |
| Closed question | A question in which the respondent is asked to select an answer from a set choice of alternative replies. |
| Cognitive | Involving the processing of information in the mind. |
| Cognitive Modelling | The modelling of the cognitive knowledge needed, and the physical actions that a user must carry out, in order to do a task. |
| Cognitive psychology | The study of how information is processed and represented in the mind. |
| Command | A form of communication with a computer system, usually via a keyboard, in which a request is made for action by inputting a short word or abbreviation. |
| Command language grammar (CLG) | An analysis technique based on grammar that describes the interface at four different, related levels. |
| Communication style | See Dialogue. |
| Computer science | The study of the construction of hardware and software, and the computer applications. |
| Computer screen | An electronically generated visual display, usually a cathode ray tube, plasma, liquid crystal or light-emitting diode display. |
| Computer-supported co-operative working (CSCW) | When two or more people work collaboratively supported by computers. |
| Concatenation | The artificial production of speech by chaining together pre-recorded units of human speech. |
| Conceptual model | See Design model |
| Contextual inquiry | An evaluation approach in whihc both users and researchers participate to identify and understand usability problems within the normal working environment of the user. |
| Contextual interview | An interview in which the user and researcher discuss user goals, ways of working and problems encountered when using a system. |
| Continuous speech recognition system | A system that can recognise key words when they are spoken in a string of other words. |
| Design model | The knowledge that a designer has about the system and the way it should work. |
| Dialogue | The exchange of instructions and information that takes place between a user and a computer system. |
| Direct manipulation | A communication style in which objects are represented on the computer screen as realistic as possible, and can be manipulated by the user in ways analogous to how the user would manipulate the real object; generally actions are reversible. |
| Distributed model | A shared model of the system in which parts of the representation are cognitively distributed amongst several people working together. |
| Electro-physiological input | A means of input in which eye movement is tracked by implanting electrodes in the eye muscles. |
| Encoding | Converting information from the environment into some form of internal, mental representation or model. |
| Ergonomic | The study of human beings in relationship to their environment, and the engineering of that environment for comfort, efficiency, and safety. |
| Evaluation method | A procedure for collecting relevant data concerning the operation of a user-computer interface. |
| Evaluation process | The gathering of information within a specified context on the usability or potential usability of an interface, and the use of that information either to imporve features within the interface and the supporting material or to assess the completed interface. |
| Feedback | The process of a system which can be often at a low level, and which indicates either that all is well or that it is not. |
| Fixed menu | A 'permanently' visible menu. |
| Flexible interview | An interview that has some topics but no set sequence, and which follows the interviewees' replies and personal attitudes. |
| Form-fill | A communication style in which the computer elicits information from the user by presenting a form, analogous to a paper form, to be filled in by the user. |
| Formative evaluation | An evaluation that takes place before implementation and which influences the development of the product. |
| GOMS | A task analysis technique which uses goals, operators, methods, and selection rules to desrcibe how a set of tasks is to be accomplished. |
| Graphical user interface (GUI) | A highly graphical interface with WIMP and direct manipulation characteristics. |
| Hierarchical task analysis (HTA) | A method that aims to describe a task in terms of a hierarchy of operations and plans. |
| Human computer interaction (HCI) | The study of how human beings interact with computers. |
| Hypermedia | Virtual media in which information is held in a network of nodes, which may have links to other nodes, and where users can decide how much of the information they want to see. |
| Hypertext | Similar to hypermedia except that hypertext contains only text with diagrams. |
| Impact analysis | A form of ranking, used to rank user problems in order of their individual contribution to the total problem time. |
| Information technology (IT) | The processing and transfer of information using technology, in particular computers. |
| Input device | Any device that transfers information from the outside world into an electronic form that the computer can use. |
| Interaction | The exchange that occurs between users and computers. |
| Isolated word recognition system | A system that can understand key words when they are spoken in isolation from other words. |
| ISDN (Integrated services digital network) | Telecommunications network on which images, text, and speech can be transmitted on the same bandwidth. |
| Likert scale | A rating scale in which the strength of agreement with a clear statement is measured. |
| Man-machine interface, MMI | An older term for human-computer interaction; it referred to many semi-automatic and automatic machines. |
| Media tool | Sets up input and output structures, linking them to low-level objects such as buttons and pop-up menus. |
| Mental model | A mental representation that a person uses to recognise her experience of herself, others, the environment, and the things with which she interacts. |
| Menu | A set of options displayed on a screen where the selection and execution of one (or more) of the options results in a change in the state of the interface. |
| Microform | A form of output in which text, and sometimes graphics, are reduced greatly in size and recorded on film. Includes microfiche and microfilm. |
| Multi-layer model | A model of an interface that uses a number of layers to bridge the gap between the high-level operations (the setting of task goals and the selection and ordering of the appropriate subtasks) and the low-level physical actions, such as command input. |
| Multimedia | An umbrella term for the integration of different media such as text, graphics, video, still photographs, and sound in a single application. |
| Multitasking | Switching between several different tasks at the interface. |
| Open question | A question in which the respondent is free to provide her own answer. |
| Organisational psychology | The study of the varying structures, cultures, and working practices of organisations and their influence on human behaviour. |
| Output device | Any device which takes the internal, electronic representation from within a computer and makes it available in theoutside world, in electronic, electrical or any other perceptible form. |
| Participative design | A method involving users that deal with a whole system, taking social and organisational requirements into account at any early stage in the development cycle. |
| Philosophy | One of the disciplines contributing to HCI, where it is primarily concerned with the impact of and ethics surrounding the introduction of IT into the world. |
| Photoelectric reflection | A means of tracking eye movement by recording reflection from the eye. |
| Pop-up menu | A menu that appears when the user clicks on a particular part of a display. |
| Printer | A device for displaying text on paper output. |
| Production rule | A formal rule of the form IF (premise) THEN (condition), to define how to produce a correct statement in a programming language; used in BNF. |
| Psychology | The study of human behaviour; psychology, and particularly its branch 'cognitive psychology', have contributed to HCI. |
| Pull-down menu | A menu that 'pulls down' like a roller blind from a title bar at the top of a display. |
| Qualitative data | Data that may be categorised in some way but are not reduced to numerical values. |
| Quantitative data | Data that can be recorded in a numerical form. |
| Question and answer dialogue | A communication style in which the computer (usually) initiates questions and the user enters yes/no or menu choices. |
| Ranked order scale | A scale that provides a way of ranking items for their usefulness. |
| Requirement analysis | An investigation to specify what the system should do (that is, the system's functionality). |
| Selective attention | The ability to take notice of one particular item of information from amongst a mass of items competing for one's attention. |
| Semantic differential scale | A scale with bi-polar adjectives (such as easy-difficult, clear-confusing) at its end points; respondents rate an interface on a scale between these paired adjectives. |
| Session tool | A management function controlling actual interaction. |
| Single-layer model | A model of an interface that produces a 'flat' representation in which small cognitive operations punctuate physical operations. |
| Social psychology | The study of human behaviour and relationships within differing social groups, and the characteristics of those groups that affect the individuals within them. |
| Sociology | The study of social groups and their dynamics; it has contributed to HCI. |
| Software engineering | A formal approach to the construction of computer software. |
| Speaker-dependent system | A speech-recognition system that can recognise words spoken by most people, regardless of differences in pitch, tone, accent, and so on. |
| Spreadsheet | A communication style analogous to an accountant's spreadsheet, but in which many functions, such as totalling rows or columns, are automated or programmable. |
| Structured design methods | Software design methods that formalise the processes involved in the phases of software development, using notations. |
| Structured interview | An interview that has predetermined questions and a set sequence of questions, and allows no exploration of individual attitudes. |
| Subtask | A part of a larger task; in system design, a task must be broken down into subtasks that are small enough to be converted to a dialogue with the computer system. |
| Summative evaluation | Any evaluation that takes place after implementation. |
| Synthesis-by-rule | The artificial production of speech through the use of rules of pronunciation, intonation, and physical characteristics of human speech. |
| System image | The image a system conveys to the user by its interface, behaviour and documentation, and which should form the basis of the user's mental model of the system. |
| System specification | An initial statement of a customer's requirements produced by software engineers. |
| Tactile output device | An output device that uses the user's sense of touch, e.g. Braille screen readers. |
| Task | An activity that a user of a computer system needs to do in order to achieve an objective. |
| Task analysis | Any of a variety of forms of analysis of how people work; involves analysing what tasks and subtasks must be done, and how they must be done, in order to achieve required onjectives. |
| Task analysis for knowledge-based descriptions (TAKD) | A task analysis method in which tasks are described in terms of the knowledge needed to do them. |
| Task-action grammar (TAG) | A task analysis method that uses a formal grammar, similar to BNF, to describe users' tasks. |
| Transition diagrams | Graphic structures indicating states and transitions from one state to another. |
| Usability | A measure of the ease with which a system can be learned or used, its safety, effectiveness and efficiency, and the attitude of its users towards it. |
| Usability engineering | An approach to system design in which the usability level of a system is specified quantitatively in advance, using metrics. |
| Usability laboratory | A small room where a subject performs tasks; it incorporates a one-way mirror in one wall so that an evaluator can observe the subject without being seen. |
| Usability metrics | The measures that are collected for describing the usability of a system. |
| Usability specification | The document that guides design by specifying usability metrics and tests. It defines the acceptable performance of the system for particular users and tasks. |
| Usability testing | Assessment of the usability of a system, in terms of learnability, ease of use, flexibility, safety, effectiveness, efficiency and the attitude of users to the system. |
| User interface | All the aspects of a computer system of which the user is aware and which the user uses to communicate with the system. |
| User models | Cognitive and performance models of the user which have been developed as design and evaluation tools. |
| User-system interaction (USI) | A similar term to, but more general than, HCI. See HCI. |
| Virtual reality | A state in which the user has the illusion of being in a three-dimensional world created by the computer system. |
| Visual output device | Any output device that uses the user's sense of sight (visual display unit); screens and paper output are the most common, although video is becoming available. |
| Window | A restricted view of data on a VDU, particularly when the VDU screen can have more than one window active, each with a different view. |
PhD Work>Usability Glossary