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Glossary and terminology

White paper: conducting user evaluations with people with disabilities

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Accessibility: An attribute of information technologies (IT) that allows the technology to be used by someone with a disability.
Accessible: Ability of a person with a disability to approach, enter, operate, participate in and/or use safely and with dignity (i.e. site facility, work environment, service, or program).
Acquired Hearing Impairment: A hearing impairment that occurs after birth, usually in adulthood.
Americans with Disabilities Act (ADA): A comprehensive Civil Rights law which makes it unlawful to discriminate against a qualified individual with a disability.
Assistive Technology (AT): Any item, piece of equipment, or product system, whether acquired commercially or off the shelf, modified, or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities.
Attention Deficit Disorders (ADD): A term frequently used to describe the academic and behavior problems of children who have difficulty focusing and maintaining attention.
Attention Span: The length of time an individual can concentrate on a task without being distracted or losing interest.
Automated Telephone System: A telephone system integrated with a computer which provides various applications, including recordings of a business's hours of operation, transportation scheduler, fees and other types of information. It is also capable of routing calls to the appropriate extension without going through an operator.
Alternative Augmentative Communication (AAC): An alternative method used to restore a person's ability to express his or her needs, thoughts and feelings. This communication may involve the use of specialized gestures, sign language or Morse code. It may also include the use of charts, special bracelets, language boards and other devices known as communication aids.


Braille: A technique whereby each of the letters of the alphabet is displayed in a pattern represented by a combination of one to six (or eight) raised dots.


Closed Caption Decoders: Devices that convert a television program's dialogue into text which appears on the TV screen and can be read by deaf and hard of hearing viewers. Starting in mid 1993, all TVs with "screens 13" or larger must include built-in closed caption decoder circuitry.
Closed Circuit TV Magnifier: Commonly known as CCTV and also called CCTV reader. System consists of a television camera, which views a printed page or other materials, and a television monitor, which display the image in larger form.
Cognitive Impairments: Reasoning, reading or comprehension difficulties, such as dyslexia or memory loss.
Communication Board: A device which resembles a keyboard. It uses letters, symbols or pictures to allow its user to communicate his or her needs or wishes to another person.
Communication Prosthesis: Any device used to communicate in place of speaking or writing. This includes speech synthesizers, switches, special symbols and graphics, and voice recognition systems.
Congenital: A condition that has been present from birth.


Digitized Speech: Human-like speech produced by a computer or computerized device.
Dyslexia: Impairment of the ability to deal with language. A person with dyslexia may see letters, syllables, or words upside down, reversed, blurred backwards or otherwise distorted.


Electronic Aids: Entire category of devices which enable individuals with speech impairments to have conversations, write and store messages, and have access to computers.
Electronic Reading Devices Electronic devices which "read" written documents using synthetic human-like speech. These devices employ optical character recognition (OCR) capabilities to scan the information on a page and transform it into audible information.
Eye Trackers: Also called eye-gazers. An infrared device which tracks movement of the eye and allows a person to communicate using a computer and synthetic voice output. The user focuses on a computer screen containing letters, words and phrases which the computer then interprets and "speaks" through a synthetic voice device or software application.


Head Pointer: Also called head stick. A stick or rod which attaches to a person's head with a band. It allows the individual to perform tasks ordinarily performed by hand or finger movements. Individuals can use head pointers to operate specially-designed computer keyboards or communication aids.
Hearing Aid: A device used to amplify sound, typically worn in the ear to amplify sound.
Hearing Impairment: A reduction or loss of hearing or speech. Heuristics: Heuristics are guidelines that form the basis of good design derived from years of research in human-computer interaction, human factors, and usability. Heuristic Evaluation: Heuristic evaluation is a proven technique for evaluating user interface designs. This technique consists of a formal inspection by a panel of expert evaluators, guided by a set of predefined guidelines. Heuristic evaluation us a good source of analytical insight. However, it is less effective than user evaluation at detecting subtle problems and delivering proof of usability problems or excellence. For this reason, usability professionals often combine heuristic evaluation and user evaluation.
High-fidelity Prototype: A high-fidelity prototype is used for demonstrating completed design iterations following evaluations and design refinement. High-fidelity prototypes need to represent the final product, so they need to be as close as possible to the true implementation of the product.


IBM Corporate Instruction (CI) 162: In 1999, IBM's Board of Directors issued this corporate instruction to direct all IBM operating organizations and subsidiaries to include accessibility features in their products, or make them compatible with assistive technologies. IBM technology is to be accessible without regard to the ability of the user.


Keyguard: A device that stabilizes the user's hand(s) on the keyboard. It prevents unintentional pressing of more than one key at a time.


Limitation of Sensation: Difficulty or inability to feel heat, touch, pain or pressure. Usually refers to an inability of the nerves to function properly.
Low-fidelity Prototype: A low-fidelity prototype is used in the evaluation of a conceptual design. The basic elements of the design are emulated using very simple methods. For example, pictures can be drawn to represent each web page and a pencil can be used instead of a mouse to simulate a user navigating through a web site.


Microsoft Active Accessibility (MSAA): A Windows application programming interface (API) that standardizes information exchange between assistive technologies, such as screen readers, and other applications.
Mobility Aids: Devices which enable physically disabled individuals to move. Example: wheelchair.
Mobility Impairment: Limitation of movement or range of motion. Can refer to poor balance, difficulty sitting or moving. For example, difficulty using mouse or keyboard. Note, though, that this is often equated with wheelchair users by many people, so should be avoided if possible.
Motor Impairment: The preferred name for mobility impairment.
Motor/Motor Control: Pertaining to the origin or execution of muscular activity. The ability to move and control one's body.
Mouth stick: A mouthpiece which serves as a pointer. Allows its user to control a computer, communication board or other device. Also called mouth wand.


On-screen keyboard: A software image of a standard or modified keyboard placed on the computer screen by software. The keys are selected by a mouse, touch screen, trackball, joystick, switch, or electronic pointing device.
Optical Character Recognition: See Electronic Reading Devices and scanner.


Persona: A persona characterizes a role which represents a user group. It represents a fictitious user in terms of their skills, goals, motivations, and other personal characteristics. A persona documents a composite of typical users' goals within the context of their skills, motivations, emotions, and behaviors, as discovered through research with users. A persona provides a model role that helps designers understand and focus on characteristics of users that are important to the design.
Pointing and Typing Aids: A category of devices which includes headsticks, mouthsticks, hand splints, light beam head pointers and other devices which enable an individual to point to objects or press keys on a switch, keyboard or communication board.
Prototype: A prototype is a representation of a design for evaluation purposes. A prototype represents key design aspects of the user experience, so that the design team may evaluate how well it matches their goals.
Person with Disability (PwD): A person who has a physical or mental impairment that substantially limits one or more of that person's major life activities, has a record of such impairment, or who is regarded as having such impairment.


Reasonable Accommodation: A modification or adjustment to a job application process or a modification to the work environment that enables a qualified applicant with a disability to be recognized and considered a qualified applicant for the position.
Rehabilitation Engineer: An expert that can help evaluate the usefulness of customized switches and devices for an individual with a disability. This also includes suggesting modifications of equipment used by the general public so that it can be used by an individual with a disability.
Robotics: Devices which perform movement tasks (reaching, turning knobs, etc.) for physically disabled individuals; artificial mobility.


Scanner: A device attached to an electronic reading device or a computer. Works like a photocopier to "read" printed material on a page, sending the information either to a built-in speaker which "tells" the user what is written or to a Braille display or printing device.
Screen Reader: A program that reads the contents of the screen aloud in a synthetic voice using a speech synthesizer.
Section 508: Section 508 is United States legislation that requires information, including software, be usable by anyone who has disabilities.
Speech Synthesizer: A device that speaks information in a synthetic human-like voice. It enables visually impaired or blind people to use a computer because assistive technology will "read" information on the screen to the user. Also called a text-to-speech (TTS) engine.
Switch: A device which controls another device. Switches allow operation of computers by using reliable muscle movements. Switches include devices such as joysticks, keyboard emulators, pedals and helmet-like head pieces which translate the user's head movements into computer commands.
Speech Limitation: Also called speech impairment; a weakening or loss of the ability to speak. An estimated two million people in the United States can hear but cannot speak properly. Various speech limitations restrict these individuals to using only slow, hard-to-understand speech or non-verbal communication such as sign language.
Synthetic Voice: A computerized voice that actually "speaks" for its user.


Tactile Display: A display which allows its user to feel the shape of each letter of the alphabet, not Braille. Can be used with a computer or a camera-type scanning device.
Task Analysis: Task Analysis is evaluating the usability of the web site or product by observing or anticipating how the product or web site will be used, and the steps taken to accomplish the tasks. Task-based analysis is an approach used to identify user errors, product misunderstandings, and other breakdowns in interaction between users and products. It is used as a tool to identify and reduce complexity and improve product usability.


Undue Hardship: With respect to the provision of an accommodation, significant difficulty or expense incurred by a covered entity, when considered in light of certain factors, such as the size, resources, nature and structure of the employer's operation.
User-Centered Design (UCD): UCD is an approach to designing ease of use into the total user experience. This user-based process places the user at the center of all design decisions made in relation to all aspects of a product or service offering.
User Engineering (UE): UE represents an enhanced form of User-Centered Design (UCD). User Engineering (a) includes the experience of multiple users in many roles across an enterprise working with various components to carry out their work and (b) uses rigorous modeling methods such as Unified Modeling Language (to analyze patterns and relationships) to design the total user experience.


Visual Cues: Messages on a computer screen that warn the user of mistakes or indicate something that would normally be indicated by sound. Examples are visual indications of errors or electronic mail messages, which would normally be indicated by a bell sound or beep.
Visual Impairment: Low or restricted vision, blindness or color blindness. Voice Dialing:Allows the operation of a phone using voice recognition instead of the manual buttons or rotary dial.
Voice Recognition: A computer's ability to recognize a voice and accepts spoken commands and data input.