Glossary » h

habituation

developing a habit, a fixed pattern of responses to given situations, which becomes fast and automatic but can lead to user errors when those patterned responses don’t apply, as in modal systems.

hacker ethic

the value system espoused by an ill-defined collection of hackers, programmers and other technologists who love working with computers. The primary value is that all information should be free, and this has been reflected in shareware and open source code…

halo effect

(graphics) the glow that appears around an antialiased image when it is placed over a background color that is different from the background used when making it antialiased. This occurs for gif images, which allow transparency, but only for an…

hand-held device

any interactive machine that is small enough to be held and carried in the hand and usually appropriate for carrying in a pocket. Usually refer to PDAs and other small information appliances.

haptic interface

a user interface based on touch, using the movements of the user as input and the sense of touch as output (both tactile and kinesthetic feedback). Examples include force feedback joysticks and Braille screen readers.

Hawthorne effect

the tendency for people to improve their performance after any change when they know their performance is being studied — a common potential confound when testing user interface changes for whether they represent an improvement or not.

HCI

human-computer interaction. The study of how people work with computers and how computers can be designed to help people effectively use them.

head-mounted display

HMD; a computer monitor or other display (such as an LED readout) that can be worn on the head so that a user can view it without looking away from the surrounding environment and without having to hold the display,…

heads-up display

an indicator, common in games, like a panel, that appears typically at the top of a display and provides status information.

healthcare information system

(HIS) computer systems designed for any of a wide variety of healthcare applications, including clinical (e.g. computer-based patient records – CPRs), financial, insurance, and medical education.

Some special issues in healthcare include safety and cleanliness of physical devices, necessary knowledge…

hearing impairment

difficulty hearing or deafness. For those who are hard of hearing, volume controls can help them use a computer, as well as output devices that enable them to plug in headphones and control the position and direction of speakers. For…

hedonic quality

(hedonism: the unrestrained pursuit of pleasure) the aspects of a user interface that appeal to a person’s desire of pleasure and avoidance of boredom and discomfort. The aspects that are fun, original, interesting, engaging, and cool. A positive subjective experience.…

help desk

an organization providing user support for computer and software use, possibly including help with installation, usability difficulties, software bugs, system administration, version and compatibility concerns, and so forth. Help desk software assists people at the help desk in retrieving answers…

heuristic

a rule of thumb. In usability evaluation, a heuristic is a guideline that works pretty well most of the time for identifying design problems, but shouldn’t be expected to cover every circumstance.

heuristic estimation

a technique where user interface evaluators make estimates of how usable a system will be on a variety of quantitative criteria, as opposed to heuristic evaluation, where they merely try to identify problems.

heuristic evaluation

a technique for finding usability problems with a user interface. A small number of trained evaluators (typically 3 to 5) separately inspect a user interface by applying a set of “heuristics”, broad guidelines that are generally relevant. They then combine…

Hick’s Law

(1) H = log2(n + 1).
(2) H = Σ pi log2(1/pi + 1).

H = the information-theoretic entropy of a decision.
n = the number of equally probable alternatives.
pi = the probability of alternative i…

hierarchical menu

a cascading menu; a menu with items that open up further submenus.

hierarchical task analysis

HTA or hierarchical task decomposition, HTD; breaking down the steps of a task (process) performed by a user, viewed at different levels of detail. Each step can be decomposed into lower-level sub-steps, thus forming a hierarchy of sub-tasks. The highest…

high-fidelity prototype

a prototype that is quite close to the final product, with lots of detail and functionality. From a user testing point of view, a high-fidelity prototype is close enough to a final product to be able to examine usability questions…

hit logs

statistics on which pages are getting visited on a website, useful for determining which pages are popular, which may be difficult to find, and which paths people are taking through the website.

The logs may contain information on what date…

homepage

the web page that visitors will usually come to first and which provides access to the remaining pages on the website. A home page is frequently accessed through the domain name of the website. Home pages are typically designed to…

horizontal and vertical prototypes

describes what types of capabilities are implemented in a prototype: horizontal prototypes display a wide range of features but without fully implementing all of those features; vertical prototypes do not attempt to show all that will be in a system…

hot-swappable device

any hardware input or output device that can be plugged into a computer or removed from it while the computer is “hot”, turned on and currently running software, so that the device can be detected and used by software and…

hotspot

the sensitive region of an image, such as the areas that are clickable on an imagemap displayed on a website, or the position on a pointer icon that indicates the exact point that is being pointed at.

hover state

the appearance or behavior of a button or other control while the pointer is over it but the item has not been clicked or dragged; most often used to hilite buttons as the pointer moves across them to indicate that…

HSV

hue-saturation-value; a color model that specifies any given color based on its hue (the frequency of light, e.g. red-orange-yellow-green-blue-violet), saturation (amount of white versus pure color), and value (intensity or brightness). Formally equivalent to other color models (RGB, HSB, CMYK),…

HTML

HypertText Markup Language; a simple notation for describing the format and content of text by adding simple annotations or “tags” to the text. HTML is the fundamental format used for presenting documents on the web.

human anthropometry

anthropometrics; the measurement of the physical characteristics of humans, particularly length and weight measures, used for industrial design, especially the design of furniture, vehicles, and workspaces. In the domain of computer use, such measurements apply primarily in the design of…

human factors

the field that studies the role of humans in human-machine systems and how systems can be designed to work well with people, particularly with regard to safety and efficiency. Traditionally this field was from an engineering and industrial design perspective…

human-computer interaction

a diverse scientific and applied field where the focus is on how people use computers and how computers can be designed to help people use them more effectively.

The subject is studied from a wide variety of perspectives from many…

human-machine interface

HMI or MMI (man-machine interface); the portion of an electro-mechanical system that a person interacts with, used most often to refer to hardware as opposed to software interfaces. The HMI is the collection of knobs, levers, and monitors that a…

hunt and peck

a level of novice typing skill characterized by the need to visually locate the letters on a keyboard as a person types, thus drastically slowing down typing speed.

hyperbolic tree

a method of displaying a hierarchy (such as a corporate org-chart or a directory structure) of any size within a finite area (a circle). The node that is focused on is centered, and as you move away from the central…

hypertext

a collection of text documents with links from one document to another. A “hypermedia” system is the same sort of collection, but including documents of any type, such as graphics, video, etc. The links may pass between essentially any two…

hysteresis

resistance to applied force, e.g. viscosity. Applied to keyboard keys and the feel of resistance they give, and appropriate to all interactions where the interface resists change, lags in response, or dampens the magnitude of the input (e.g. an icon…