Glossary » r

racing stripes

close parallel lines used to indicate that a control is draggable, similar to the way that parallel bumps are used on physical devices, such as sliding switches, to provide grip and tactile feedback. Racing stripes are most familiar in the…

RAD

a Rapid Application Development tool. These are tools, such as Visual Basic and Delphi, which are designed to make developing software applications a faster process, usually by focusing on the design of the user interface in terms of screen layout…

radar view

an indicator in a display that shows an overview, such as a map, with indicators of activities. In multi-user systems, the radar would indicate the positions of other people and possibly information about their activities.

radio button

based on the metaphor of buttons on a car radio (for selecting a radio station), a radio button is a small button in a group of buttons where only one button can be selected at a time (unlike a checkbox).…

random observation

a type of field study to gather usage data, where you observe users at random points throughout the day to see what they’re doing with your software at those times, thus capturing real-life as opposed to laboratory usage. Random observation…

rapid prototyping

quickly generating mockups of what a system will look like. Rapid prototyping may be done with paper prototyping methods, such as with quick sketches, or with techniques like video prototyping or wizard of oz prototyping. Rapid prototyping systems are software…

raster display

the standard technology for computer monitors that display images on a grid of pixels, allowing the computer to light up any individual pixel easily, and enabling color displays by having individual red, green, and blue (RGB) phosphors at each pixel…

reaction time

a measure of a user’s delay in executing an action after being prompted. While it may measure “task time”, reaction time is usually used to refer to quick responses that do not require substantial mental processing (though the whole point…

readability

the degree to which the meaning of text is accessible, based on the complexity of sentences and the difficulty of the vocabulary that is used. Readability indexes usually rank usability by the age or grade level required for someone to…

readme file

a file often included with a software release called “README” (or “readme.txt” or something similar) that provides information on installation, upgrades and versions, compatibility, and other product documentation that was too last-minute to make it into the printed documentation.

realtime groupware

software used to help people to work in groups, while working together at the same time. Examples include phones and videoconferencing, playing arcade games together, and shared drawing tools that allow people to see what their conversational partners are drawing…

recall

in information retrieval, a measure of the quality of search results. High recall means a large number of matches is returned for a search (though not all matches may be particularly good matches).

reciprocity

a design principle that suggests that users of a communications system should be on equal terms, for instance, by allowing one person to see the video of another only if the other can also see the video of the first.…

recommender system

a system that recommends apparently useful information or suggests strategies users might apply to achieve their apparent goals. A recommendation may come up based on a given event, such as an error, or may be based on watching a user’s…

redundant coding

or secondary coding; representing information in more than one way so that users have more than one opportunity to perceive and understand it, to reinforce the information, to make the information more accessible (because one representation may not work for…

redundant modalities

using more than one way to represent, display, and enter data, such as:

…

regression testing

after repairing a problem identified in a previous test, re-testing to confirm not only that the problem has been fixed but that no other problems have been introduced in the process. Regression testing is common when fixing software bugs but…

rehabilitation engineering

the field that explores the design of assistive devices for the disabled and customizes those devices for individual needs.

relevance

in search, relevance is a measure of the quality of a search result, indicating how close the search result is to the information being sought. Relevance is often measured, for instance, by the number of times a search term occurs…

reminder system

a system for alerting a user to important items on a schedule, after a timeout, or when a critical event happens. Used, for instance, in a medical setting to remind clinicians of necessary tests or interventions. Useful especially to people…

remote usability evaluation

situations where the user and the usability evaluator are not located in the same place, as when users are tested over the internet. Remote evaluation is especially helpful when the user population is small and specialized, dispersed, or difficult to…

replicated architecture

an architecture for distributed applications that uses identical copies of software running at each users station with identical views of the application for each user.

requirements analysis

an early phase in user interface design where basic requirements are determined. Typical categories of requirements include target audience and target platform, features of the application, responsiveness, usability benchmarks (e.g. “such and such a task must be completed within 2…

resize box

the small box, usually at the bottom-right of a window, used to change the size of the window by dragging it to the desired size.

resize corner

a special region at the corner of a window, used to change the size of the window by dragging it to the desired size. While resize boxes are usually just at the bottom-right, resize corners are at all 4 corners…

resize handle

a small box that appears at each of the corners of a selected object (and sometimes at the sides also) that can be dragged to alter the size of the object.

resource bundle

the portion of a piece of software that holds application data (but not user data) separate from the program itself. Typical resources include icons, window positions, dialog box definitions, program text, and menus. The resource bundle is a convenient way…

response time

time between receiving a stimulus and delivering an appropriate response or reaction. System response time is how long it takes the computer to respond to a user command, or the length of time, for instance, to download a web page…

responsiveness

the degree to which a user perceives a system as reacting quickly to user input. Responsiveness is not the same as speed. Slow systems can be perceived as highly responsive if they consistently provide quick feedback to users. This can…

retrospective testing

additional “testing” after-the-fact. After a user testing session has been conducted and videotaped, retrospective testing is reviewing the tape with the user to ask additional questions and get further clarification.

reversible actions

any action that can be undone. Reversibility is a design principle that says people should be able to recover from their inevitable mistakes. Dialog boxes should have a Cancel button. Applications should have an Undo feature (and possibly multiple undo,…

RGB

red-green-blue; a common color model used especially in CRTs which specifies any given color as a combination of 3 brightness values for red, green, and blue elements. While theoretically equivalent to other color models (HSV, HSB, CMYK), the RGB makes…

robot

a piece of software that actively browses the web, retrieving and analyzing documents, usually used to collect and index documents for search engines.

ROI

return on investment. A measure of the value of making an investment. Spending money on information systems development, and on usability in particular, means providing a rationale for how the project will be managed to achieve maximum return, i.e. providing…

role

a means of expressing that participants in a conversation come with different skills and interests and should have a user-interface that reflects their personal needs.

Roles such as chairperson, scribe, and facilitator reflect a set of access capabilities to shared…

role-playing walkthrough

a method for evaluating a user interface, particularly one where multiple people may be interacting during its use, such as customer service applications (cash registers, telemarketing) and groupware. Each person in the evaluation team acts the part of a user…

rollovers

actions that occur as a user moves a pointer over objects, such as the hiliting of buttons as a user moves over them, in order to indicate that they are clickable, and also sometimes used to provide additional information (such…

rough

(graphic design) a rapidly-drawn sketch, larger and more detailed than a thumbnail sketch, but less refined and precise than a comp, used to explore visual possibilities in design.

router page

a web page whose primary role is to route the user to another appropriate page. Examples include homepages, sitemaps, and portal sites. Often homepages and main section pages should not solely serve a routing function but should include useful information…

routing slip

a type of dialog box for routing information (a file or email) with a specified sender, recipient, data format, and transmission medium (NewtonOS term).

RSI

repetitive stress injury; injuries resulting from excessive repeated movement with little variation, such as typing and mousing. RSI can result from many activities (such as assembly line work), and interacting with computers is only one manifestation. Damage occurs to soft…

RSVP

a mnemonic for requirements analysis – structural design – visual design – production, the main steps in a design process. In the spirit of iterative design, each stage would have an evaluation component to ensure that the design was proceeding…

rubberbanding

when creating or resizing graphics, such as a rectangle or oval, the way it stretches, like a rubberband, to follow the pointer as you drag it.

ruggedized device

a piece of hardware designed for abuse, such as adverse environments and usage. For instance, ruggedization might be useful in industrial settings, outdoor work, sports, emergency uses, or rough handling by children. Ruggedizing may include techniques such as rubber components,…