A great resource for designers of every kind. It's filled with concepts of psychology, architecture, human factors and interaction design.
The concepts in this book, broadly referred to as “principles,” consist of laws, guidelines, human biases, and general design considerations.
A property in which the physical characteristics of an object or environment influence its function.
e.g. Stairs are better suited than fences for climbing; therefore, stairs are said to better afford climbing.
Images of common physical objects and environments can enhance the usability of a design. For example, a drawing of a three-dimensional button on a computer screen leverages our knowledge of the physical characteristics of buttons and, therefore, appears to afford pressing.
A tendency to see attractive people as more intelligent, competent, moral, and sociable than unattractive people.
For example, in studies presenting images of attractive and unattractive people to babies (two-months-old and six-months-old), the babies looked longer at the attractive people regardless of their gender, age, or race.
A tendency to see people and things with baby-faced features as more naïve, helpless, and honest than those with mature features.
A technique of combining many units of information into a limited number of units or chunks, so that the information is easier to process and remember.
The maximum number of chunks that can be efficiently processed by short-term memory is four, plus or minus one.
Chunk information when people are required to recall and retain information, or when information is used for problem solving. Do not chunk information that is to be searched or scanned.
Familiar words are easier to remember and chunk together than unfamiliar words.
Chunking large strings of numbers into multiple, smaller strings can help.
A technique used to associate a stimulus with an unconscious physical or emotional response.
Because the lab workers feed the dogs, their presence (neutral stimulus) had become associated with food (trigger stimulus), and, therefore, elicited the same response as the food itself (salivation).
Classical conditioning is commonly used in animal training (e.g., associating chemical traces of TNT with sugar water to train bees to detect bombs), behavior modification in people (e.g., associating smoking with aversive images or tastes), and marketing and advertising (i.e., associating products or services with attractive images or feelings).
behavior modification in people (e.g., associating smoking with aversive images or tastes),
Use classical conditioning to influence the appeal of a design or influence specific kinds of behaviors. Repeated pairings of a design with a trigger stimulus will condition an association over time.
Cognitive dissonance is the state of mental discomfort that occurs when a person’s attitudes, thoughts, or beliefs (i.e., cognitions) conflict.
The usability of a system is improved when similar parts are expressed in similar ways.
Successful products typically follow four stages of creation:
A point of physical or attentional entry into a design. People do judge books by their covers.
An action or omission of action yielding an unintended result.
A phenomenon in which perception and behavior changes as a result of personal expectations or the expectations of others. (e.g. halo effect, placebo effect)
Repeated exposure to stimuli for which people have neutral feelings will increase the likeability of the stimuli.
The ratio of face to body in an image that influences the way the person in the image is perceived.
As the flexibility of a system increases, its usability decreases.
Flexible designs can perform more functions than specialised designs, but they perform the functions less efficiently.
Designs should help people avoid errors and minimise the negative consequences of errors when they do occur. ****(e.g. undo, back-ups, roll-backs).
The quality of system output is dependent on the quality of system input.
The best way to avoid garbage out is to prevent garbage in. Use affordances and constraints to minimise problems of type. Use previews and confirmations to minimise problems of quality.
A ratio within the elements of a form, such as height to width, approximating 0.618.86
Geometries of a design should not be contrived to create golden ratios, but golden ratios should be explored when other aspects of the design are not compromised.
A diagram that describes the general pattern followed by the eyes when looking at evenly distributed, homogeneous information.
The time it takes to make a decision increases as the number of alternatives increases.
For example, when a pilot has to press a particular button in response to some event, such as an alarm, Hick’s Law predicts that the greater the number of alternative buttons, the longer it will take to make the decision and select the correct one.
The use of pictorial images to improve the recognition and recall of signs and controls.
There are four types of iconic representation:
A phenomenon in which mental processing is made slower and less accurate by competing mental processes.
The visual clarity of text, generally based on the size, typeface, contrast, text block, and spacing of the characters used.
All products progress sequentially through four stages of existence:
A technique used to modify behaviour by reinforcing desired behaviours, and ignoring or punishing undesired behaviours.
Use operant conditioning in design contexts where behavioural change is required. Focus on positive or negative reinforcement, rather than punishment whenever possible.
Memory for recognising things is better than memory for recalling things.
It is easier to recognise things than recall them because recognition tasks provide memory cues that facilitate searching through memory.
A tendency to assume that a system that works at one scale will also work at a smaller or larger scale.
An ant scaled to human size would only be able to lift about 50 pounds, assuming it could move at all. The effect of gravity at small scales is minuscule, but the effect increases exponentially with the mass of an object.
A technique used to teach a desired behavior by reinforcing increasingly accurate approximations of the behavior.
A method of creating imagery, emotions, and understanding of events through an interaction between a storyteller and an audience.
A tendency to interpret shaded or dark areas of an object as shadows resulting from a light source above the object.
Interestingly, there is evidence that objects look most natural and are preferred when lit from the top-left, rather than from directly above. This effect is stronger for right-handed people than left-handed people, and is a common technique of artists and graphic designers.
The process of using spatial and environmental information to navigate to a destination.