Notes for Donald A. Norman The Design of Everyday Things
Key concepts: affordance, connectionism, design model, forcing functions, mapping, paradox of technology, power of constraints, stickiness of memory, taught helplessness, user's model.
Designer versus user model. Compare knowledge in the world to explicit versus implicit knowledge. Also consider 'stickiness' of memory when what is being learned relates or does not relate to the overall context of activities of which the learning is a part. Recall von Neumann's discussions about error tolerance of natural and artificial automata. Interesting categorization of slips. Suggests the ideal computer is invisible. Heim would argue strongly against this equivocating the computer as an ordinary tool. Norman's recommendation of designing software such that the computer disappears and the task is foregrounded allows concealing of enframing. “A worn sock is better than a mended one; not so with metaphysics.” Reaches similar conclusions as Heim but not at the same depth of ontological analysis.
Related theorists: Heim, Ong, von Neumann.
PREFACE TO THE 2002 EDITION
Would we dare apply Normans arguments to the creation of texts beyond his own self criticism of choice of titles; clearly yes, for that is the impetus of Barker task-oriented software documentation.
(vii) Far too many items in the world are designed, constructed, and foisted upon us with no understanding - or even care - for how we will use them. Calling something a “Norman door” is recognition of the lack of attention paid by the maker to the user, which is precisely my message.
This seems like a generalization designed to suit his purpose; are the majority of automobile accidents really the result of poor design: the admission, then, is that we routinely engage in risky behavior due to the poor designs in our environment that we cannot really avoid.
(viii) The problems sound trivial, but they can mean the difference between pleasure and frustration. The same principles that make these simple things word well or poorly apply to more complex operations, including ones in which human lives are at stake. Most accidents are attributed to human error, but in almost all cases the human error was the direct result of poor design.
The Hidden Frustrations of Everyday Things
The Book Title: A Lesson in Design
(x) I talked with book buyers and clerks. My editor was correct: I needed to change the word “psychology” to “design.” In titling my book, I had been guilty of the same shortsightedness that leads to all those unusable everyday things!
Lessons from DOET
(x) the appearance of the device must provide the critical clues required for its proper operation - knowledge has to be both in the head and in the world.
(xi) The device must explain itself. Even the location and operation of the controls require a conceptual model - an obvious and natural relationship between their location and the operation they control so you always known which control does what (in the book I call this a “natural mapping”).
(xiv) Appropriate, human-centered design requires that all the considerations be addressed from the very beginning, with each of the relevant design disciplines working together as a team.
Technology Changes Rapidly; People Change Slowly
(xiv) in selecting examples, I deliberately kept away from high technology, looking instead at everyday things, things that have been around a while. High technology changes rapidly, but everyday life changes slowly.
(xv) Each time a new technology comes along, new designers make the same horrible mistakes as their predecessors. Technologists are not noted for learning from the errors of the past. They look forward, not behind, so they repeat the same problems over and over again.
(xvii) Humans do not always err. But they do when the things they use are badly conceived and designed. Nonetheless, we still see human error blamed for all that befalls society.
(xix) A major argument in POET is that much of our everyday knowledge resides in the world, not in the head. . . . People certainly do rely upon the placement and location of objects, upon written texts, upon the information contained within other people, upon the artifacts of society, and upon the information transmitted within and by a culture. There certainly is a lot of information out there in the world, not in the head.
THE PSYCHOPATHOLOGY OF EVERYDAY THINGS
Would Need an Engineering Degree to Figure This Out
(2)(figure 1.1) Carelman's Coffeepot for Masochists. The French artist Jacques Carelman in his series of books Catalogue d'objets introuvables (Catalong of unfindable objects) provides delightful examples of everyday things that are deliberately unworkable, outrageous or otherwise ill-formed.
Frustrations of Everyday Life
(4) The correct parts must be visible, and they must convey the correct message. With doors that push, the designer must provide signals that naturally indicate where to push. . . . The vertical plate and supporting pillars are natural signals, naturally interpreted, without any need to be conscious of them. I call the use of natural signals natural design.
(5) Other problems concern the mappings between what you want to do and what appears possible.
(8) Visibility indicates the mapping between intended actions and actual operations.
The Psychology of Everyday Things
Definition of affordance as perceived or actual property determining range of uses.
(9) affordance refers to the perceived and actual properties of the thing, primarily those fundamental properties that determined just how the thing could possibly be used.
THOUSAND EVERYDAY THINGS
(12) Here is where the designer's knowledge of the psychology of people coupled with knowledge of how things work becomes crucial.
Principles of Design for Understandability and Usability
PROVIDE A GOOD CONCEPTUAL MODEL
Conceptual models include design model, users model, and resulting system images.
(16)(figure 1.10) Conceptual Models. The design model is the designer's conceptual model. The user's model is the mental model developed through interaction with the system. The system image results from the physical structure that has been built (including documentation, instructions, and labels). . . . If the system image does not make the design model clear and consistent, then the user still end up with the wrong mental model.
(22) Whenever the number of possible actions exceeds the number of controls, there is apt to be difficulty.
PRINCIPLE OF MAPPING
(23) Mapping is a technical term meaning the relationship between two things, in this case between the controls and their movements and the results in the world.
(23) Natural mapping, by which I mean taking advantage of physical analogies and cultural standard, leads to immediate understanding.
(25) A device is easy to use when there is visibility to the set of possible actions, where the controls and displays exploit natural mappings.
PRINCIPLE OF FEEDBACK
(27) Feedback - sending back to the user information about what action has actually been done, what result has been accomplished - is a well-known concept in the science of control and information theory.
Paradox of technology that added complexity accompanies added functionality.
(27) To be fair, these new designs are pushing hard on the paradox of technology: added functionality generally comes along at the price of added complexity.
Pity the Poor Designer
Paradox of Technology
(30) The development of a technology tends to follow a U-shaped curve of complexity: starting high; dropping to a low, comfortable level; then climbing again.
(31) Whenever the number of functions and required operations exceeds the number of controls, the design becomes arbitrary, unnatural, and complicated. The same technology that simplifies life by providing more functions in each device also complicates life by making the device harder to learn, harder to use. This is the paradox of technology.
THE PSYCHOLOGY OF EVERYDAY ACTIONS
Falsely Blaming Yourself
(36) If an error is possible, someone will make it. The designer must assume that all possible errors will occur and design so as to minimize the chance of the error in the first place, or its effects once it gets made. Errors should be easy to detect, they should have minimal consequences, and, if possible, their effects should be reversible.
Misconceptions of Everyday Life
ARISTOTLE'S NAIVE PHYSICS
AS EXPLANATORY CREATURES
(39) everyone forms theories (mental models) to explain what they have observed. In the case of the thermostat, the design gives absolutely no hint as to the correct answer. In the absence of external information, people are free to let their imaginations run free as long as the mental models they develop account for the facts as they perceive them.
the Wrong Cause
(40) The psychology of blame (or, to be more accurate, of attribution) is complex and not fully understood. In part, there seems to have to be some perceived causal relationship between the thing being blamed and the result. The word perceived is critical: the causal relationship does not have to exist; the person simply has to think it is there.
(41) Interestingly enough, the common tendency to blame ourselves for failures with everyday objects goes against normal attributions people make. In general, it has been found that people attribute their own problems to the environment, those of other people to their personalities.
One of the foils of ambition, taught helplessness processes evident in mathematics curriculum and also with technologies.
(43) Or consider the normal mathematics curriculum, which continues relentlessly on its way, each new lesson assuming full knowledge and understanding of all that has passed before. Even though each point may be simple, once you fall behind it is hard to catch up. The result: mathematics phobia. Not because the material is difficult, but because it is taught so that difficulty in one stage hinders further progress. The problem is that once failure starts, it soon generalizes by self-blame to all of mathematics. Similar processes are at work with technology. The vicious cycle starts: if you fail at something, you think it is your fault. Therefore you think you can't do the that task. As a result, next time you have to do the task, you believe you can't so you don't even try.
The Nature of Human Thought and Explanation
How People Do Things: The Seven Stages of Action
Seven stages of action for how people do things provides basic checklist for design aids, routing around gulfs of execution and evaluation.
(48) Forming the goal; Forming the intention; Specifying an action; Executing the action; Perceiving the state of the world; Interpreting the state of the world; Evaluating the outcome.
The Gulfs of Execution and Evaluation
THE GULF OF EXECUTION
(51) The difference between the intentions and the allowable actions is the Gulf of Execution.
THE GULF OF EVALUATION
(51) The Gulf of Evaluation reflects the amount of effort that the person must exert to interpret the physical state of the system and to determine how well the expectations and intentions have been met.
The Seven Stages of Action as Design Aids
(52) The seven-stage structure can be a valuable design aid, for it provides a basic checklist of questions to ask to ensure that the Gulfs of Evaluation and Execution are bridged.
KNOWLEDGE IN THE HEAD AND IN THE WORLD
(54-55) not all of the knowledge required for precise behavior has to be in the head. It can be distributed - partly in the head, partly in the world, and partly in the constraints of the world. Precise behavior can emerge from imprecise knowledge for four reasons: 1. Information in the world 2. Great precision is not required 3. Natural constraints are present 4. Cultural constraints are present.
(56) There is a tradeoff between the amount of mental knowledge and the amount of external knowledge required in performing tasks.
Precise Behavior from Imprecise Knowledge
IS IN THE WORLD
(56) There is a tradeoff between speed and quality of performance and mental effort.
Compare knowledge in head and in the world to explicit versus implicit knowledge.
(57-58) People function through their use of two kinds of knowledge: knowledge of and knowledge how. Knowledge of – what psychologists call declarative knowledge – includes the knowledge of facts and rules. . . . Declarative knowledge is easy to write down and to teach. Knowledge how – what psychologists call procedural knowledge – is the knowledge that enables a person to perform music, to stop a car smoothly with a flat tire on an icy road . . . Procedural knowledge is difficult of impossible to write down and difficult to teach. It is best taught by demonstration and best learned through practice.
GREAT PRECISION IS NOT REQUIRED
THE POWER OF CONSTRAINTS
Point also made by Ong about power of constraints; more important is inconsideration (unthought) of audio virtual realities created by unnatural code.
(60) Combining the two constraints of rhyme and meaning can therefore reduce the information about the particular word that must be kept in memory to nothing; as long as the constraints are known, the choice of word can be completely determined.
Also consider stickiness of memory when what is being learned relates or does not relate to the overall context of activities of which the learning is a part; see page 67 on the difficulty with organizing long term memory.
(61) The notion that someone should be able to recite word for word is relatively modern. Such a notion can be held only after printed texts become available; otherwise who could judge the accuracy of a recitation?
Testing an ordering of hyperlinks through the public content leads to editing the notes for Johnson after seeing multiple links between earlier, banal analysis of stickiness of memory to recent banal work on long term memory creation and maintenance that should be applied to UCF ignoring Moodle.
Both Johnson and Ong nod toward alien phenomenology expressing state of the art methodology in digital humanities scholarship including for critical theory and invention in texts and technology.
(61) Most of us do not learn epic poems. But we do make use of strong constraints that serve to simplify what must be retained in memory. Consider an example from a completely different domain: taking apart and reassembling a mechanical device.
Memory is Knowledge in the Head
THE CONSPIRACY AGAINST MEMORY
STRUCTURE OF MEMORY
(67) The difficulty with LTM is in organization – in getting material in and in figuring out how to retrieve it – not in capacity. Storage and retrieval are easier when the material makes sense, when it fits into what is already known.
(67) If we examine how people use their memories and how they retrieve information, we discover a number of categories: Memory for arbitrary things, Memory for meaningful relationship, Memory through explanation.
MEMORY FOR ARBITRARY THINGS
Relate this and challenges of LTM to stickiness of memory discussion in research paper from Project Management for Technical Writers.
(67) Arbitrary knowledge can be classified as the simple remembering
of what is to be done, without reliance on an understanding of why or
on internal structure.
(68) People who have learned to use computers or cook by rote are probably not very good. Since they do not understand the reasons for their actions, they must find tasks arbitrary and strange. When something goes wrong, they don't know what to do (unless they've memorized solutions).
MEMORY FOR MEANINGFUL RELATIONSHIPS
MEMORY THROUGH EXPLANATION
(70) People probably make up mental models for most of the things they do. This is why designers should provide users with appropriate models: when they are not supplied, people are likely to make up inappropriate ones.
Memory Is Also Knowledge in the World
Is this the distinction Plato intends in Phaedrus, that reminding involves knowledge in the world, or the two aspects signal and message?
(72) One of the most important and interesting aspects of the role of
external memory is reminding, a good example of the interplay between
knowledge in the head and in the world.
(73) A good reminding method is to put the burden on the thing itself.
(73) There are two different aspect to reminder: the signal and the message.
(74) I am waiting for the day when portable computers become small enough that I can keep one with me at all times.
(75) The arrangement of burners and controls on the kitchen stove provides a good example of the power of natural mappings to reduce the need for information in memory.
(78) Wherever labels seem necessary, consider another design.
(78) Usability is not often thought of as a criterion during the purchasing process.
The Tradeoff between Knowledge in the World and in the Head
(80) Reminders provide a good example of the relative tradeoffs between the roles of internal versus external knowledge. Knowledge in the world is accessible. . . . Knowledge in the mind is ephemeral.
KNOWING WHAT TO DO
A Classification of Everyday Constraints
(84) for different classes of constraints - physical, semantic, cultural, and logical. These classes are apparently universal, appearing in a wide variety of situations, and sufficient.
(84) Physical limitations constrain possible operations. . . . The value of physical constraints is that they rely upon properties of the physical world for their operation; no special training is necessary.
(85) Semantic constraints rely upon the meaning of the situation to control the set of possible actions. . . . Semantic constraints rely upon our knowledge of the situation and of the world.
(85) Cultural issues are at the root of many of the problems we have with new machines: there are as yet no accepted conventions or customs for dealing with them.
(85-86) guidelines for cultural behavior are represented in the mind by means of schemas, knowledge structures that contain the general rules and information necessary for interpreting situations and for guiding behavior.
(86) Natural mappings work by providing logical constraints. There are no physical or cultural principles here; rather there is a logical relationship between the spatial or functional layout of components and the tings that they affect or are affected by.
Applying Affordances and Constraints to Everyday Objects
THE PROBLEM WITH DOORS
THE PROBLEM WITH SWITCHES
WHICH SWITCH CONTROLS WHICH FUNCTION?
HOW ARE THE SWITCHES ARRANGED?
Visibility and Feedback
MAKING VISIBLE THE INVISIBLE
(101) Nothing succeeds like visual feedback, which in turn requires a good visual display.
USING SOUND FOR VISIBILITY
(103) Natural sounds reflect the complex interaction of natural objects.
(103) If they are to be useful, sounds must be generated intelligently, with an understanding of the natural relationship between the sounds and the information to be conveyed.
(103) One of the virtues of sounds is that they can be detected even when attention is applied elsewhere. But this virtue is also a deficit, for sounds are often intrusive.
TO ERR IS HUMAN
Recall von Neumann discussions about error tolerance of natural and artificial automata.
(105) People make errors routinely. Hardly a minute of normal
conversation can be by without a stumble, a repetition, a phrase
stopped midway through to be discarded or redone. Human language
provides special mechanisms that make corrections so automatic that
the participants hardly take notice; indeed, they may be surprised
when errors are pointed out. Artificial devices do not have the same
tolerance. Push the wrong button, and chaos may result.
(105) Slips result from automatic behavior, when subconscious actions that are intended to satisfy our goals get waylaid en route. Mistakes result from conscious deliberations.
(105) Form an appropriate goal but mess up in the performance, and you've made a slip. . . . Form the wrong goal, and you've made a mistake.
Footnote on Sherry Turkle The Second Self confirms that Freud slips are reinterpreted.
(106) Some slips may indeed have hidden, darker meanings, but most
are accounted for by rather simple events in our mental
(106) Slips show up most frequently in skilled behavior. . . . On the whole, people can consciously attend to only one primary thing at a time. . . . We can do more than one thing at a time only if most of the actions are done automatically, subconsciously, with little or no need for conscious attention.
TYPES OF SLIPS
This is an excellent enumeration of six types of slips but not doing justice to Freuds insight into their nature; Freud would certainly pay attention to all types of slips, not just associative action errors.
can place slips into one of six categories: capture errors,
description of errors, data-driven errors, associative activation
errors, loss-of-activation errors, and mode errors.
(107) The capture error appears whenever two different action sequences have their initial stages in common, with one sequence being unfamiliar and the other being well practiced. Seldom, if ever, does the unfamiliar sequence capture the familiar one.
(108) Description errors usually result in performing the correct action on the wrong object.
(108) Description errors occur most frequently when the wrong and right objects are physically near each other.
(109) Automatic actions are data driven - triggered by the arrival of the sensory data. But sometimes data-drive activities can intrude into an ongoing action sequence, causing behavior that was not intended.
(109) Associate activation errors are the slips studied by Freud; you think something that ought not to be said and then, to your embarrassment, you say it.
(110) Lack-of-activation errors occur because the presumed mechanism - the “activation” of the goals - has decayed. The less technical but more common term would be “forgetting.”
How about some examples of human equivalents of mode errors: different uses of body parts, for example, for sex?
(110) Mode errors occur when devices have different modes of operation, and the action appropriate for one mode has different meanings in other modes. Mode errors are inevitable any time equipment is designed to have more possible actions than it has controls or displays, so the controls must do double duty.
(110-111) detection can only take place if there is feedback. . . . Some trail of the sequence of actions that was performed is valuable.
(111) The most global description (the one at the top of the list), is called the high-level specification. The more detailed descriptions, the ones at the bottom of the list, are called the low-level specifications. Any one of them might be in error.
(112) In all the situations I have examined the error correction mechanism seems to start at the lowest possible level and slowly works its way higher.
DESIGN LESSONS FROM THE STUDY OF SLIPS
(113) In computer systems, it is common to prevent errors by requiring confirmation before a command will be executed, especially when the action will destroy a file. But the request is ill timed; it comes just after the person has initiated the action and is still fully content with the choice. . . . The user has requested deletion of the wrong file but the computer's request for confirmation is unlikely to catch the error; the user is confirming the action, not the file name. Thus asking for confirmation cannot catch all slips. It would be more appropriate to eliminate irreversible actions.
(114) When you build an error-tolerant mechanism, people come to rely upon it, so it had better be reliable.
Mistakes as Errors of Thought
MODELS OF HUMAN THOUGHT
(114-115) Even though principles of rationality seem as often violated as followed, we still cling to the notion that human thought should be rational, logical, and orderly. . . . Many scientists who study artificial intelligence use the mathematics of formal logic - the predicate calculus - as their major tool to simulate thought.
(115) But human thought - and its close relatives, problem solving and planning - seem more rooted in past experience than in logical deduction. Mental life is not neat and orderly. It does not proceed smoothly and gracefully in neat, logical form. Instead, it hops, skips, and jumps its way from idea to idea. . . . it is the difference that leads to creative discovery and to great robustness of behavior.
(115) Human memory is most definitely not like a set of photographs or a tape recording. It mushes things together too much, confuses one event with another, combines different events, and leaves out parts of individual events.
File cabinet model of human thought.
(115-116) Another theory is based on the filing cabinet model, wherein there are lots of cross references and pointers to other records. . . . Of course, it is not called a file cabinet theory. It goes by the names of “schema theory,” “frame theory,” or sometimes “semantic networks” and “propositional encoding.” The individual file folders are defined in the formal structure of the schemas or frames, and the connections and associations among the individual records make the structure into a vast and complex network. The essence of the theory consists of three beliefs, all reasonable and supported by considerable evidence: (1) that there is logic and order to the individual structures (this is what the schema or frame is about); (2) that human memory is associative, with each schema pointing and referring to multiple others to which it is related or that help define the components (thus the term “network”); and (3) that much of our power for deductive thought comes from using the information in one schema to deduce the properties of another (thus the term “propositional encoding”).
(116) A newer approach is rooted in the working of the brain itself. Those of us who follow this new approach call it “connectionism,” but it also goes under the names of “neural nets,” “neural models,” and “parallel distributed processing.” .. This approach follows the rules of thermodynamics more than it does the rules of logic.
Interactions as computational part of thought under connectionist approach.
can think of the interactions as the computational part of thought:
when one set of units sends signals activating another, this can be
interpreted as offering support for a cooperative interpretation of
events; when one set of units sends signals suppressing another, it
is because the two usually offer competing interpretations. The
result of all this support and competition is a compromise: not the
correct interpretation, simply one that is as consistent as possible
with all possibilities under active consideration. This approach
suggests that much of thought results from a kind of pattern matching
system, one that forces its solutions to be analogous to past
experiences, and one that does not necessarily follow the formal
rules of logical inference.
(118) Throw everything into memory on top of one another. That is a crude approximation of the connectionist approach to memory.
(118) We must together details of things that are similar, and give undue weight to the discrepant. We relish discrepant and unusual memories.
(119) This event-based reasoning is powerful, yet fundamentally flawed. Because thought is based on what can be recalled, the rare event can predominate.
The Structure of Tasks
WIDE AND DEEP STRUCTURES
(121) Everyday structures are either shallow or narrow.
(121) There are many alternative actions, but each is simple; there are few decisions to make after a single top-level choice.
(121) If each possibility leads to only one or tow further choices, then the resulting tree structure can be said to be narrow and deep.
(123) Any task that involves a sequence of activities where the action to be done at any point is determined by its place in the sequence is an example of a narrow structure.
THE NATURE OF EVERYDAY TASKS
Conscious and Subconscious Behavior
(125) Subconscious thought is biased toward regularity and structure, and it is limited in formal power. It may not be capable of symbolic manipulation, of careful reasoning through a sequence of steps.
(126) Conscious thought tends to be slow and serial. Conscious processing seems to involve short-term memory and is thereby limited in the amount that can be readily available.
(127) Which is exactly what everyday tasks ought to be - boring, so that we can put our conscious attention on the important things of life, not the routine.
EXPLAINING AWAY ERRORS
(128) When there is a devastating accident, people's explaining away the signs of the impending disaster always seems implausible to others.
SOCIAL PRESSURES AND MISTAKES
(129) In industrial settings social pressures can lead to misinterpretations, mistakes, and accidents. For understanding mistakes, social structure is every bit as essential as physical structure.
Designing for Error
(131) Designers make the mistake of not taking error into account. Inadvertently, they can make it easy to err and difficult or impossible to discover error or to recover from it. . . . Don't think of the user as making errors; think of the actions as approximations of what is desired.
(131) Design so that errors are easy to discover and corrections are possible
TO DEAL WITH ERROR - AND HOW NOT TO
(132) Warnings and safety methods must be used with care and intelligence, taking into account the tradeoffs for the people who are affected.
Forcing functions: interlocks, lockins, lockouts constrain action so failure at one stage prevents next step.
Forcing functions are a form of physical constraint: situations in
which the actions are constrained so that failure at one stage
prevents the next step from happening.
(125) Forcing functions are the extreme case of strong constraints that make it easy to discover erroneous behavior. . . . In the field of safety engineering, forcing functions show up under other names, in particular as specialized methods for the prevention of accidents. Three such methods are interlocks, lockins, and lockouts.
(137) Forcing functions almost always are a nuisance in normal usage. The clever designer has to minimize the nuisance value while retaining the safety, forcing-function mechanism, to guard against the occasional tragedy.
A Design Philosophy
Design philosophy should treat interaction as cooperative endeavor between person and machine taking into account possible misconceptions arising on either side: symbiotic components versus alien opponents.
(140) The designer shouldn't think of a simple dichotomy between errors and correct behavior; rather, the entire interaction should be treated as a cooperative endeavor between the person and machine, one in which misconceptions can arise on either side. This philosophy is much easier to implement on something like a computer which has the ability to make decisions on its own than on things like doors and power plants, which do not have such intelligence. . . . Put the required knowledge in the world. . . . Use the power of natural and artificial constraints: physical, logical, semantic, and cultural. Use forcing functions and natural mappings. Narrow the gulfs of execution and evaluation.
THE DESIGN CHALLENGE
The Natural Evolution of Design
FORCES THAT WORK AGAINST EVOLUTIONARY DESIGN
(142) Natural design does not work in every situation; there must be enough time for the process to be carried out, and the item must be simple.
THE TYPEWRITER: A CASE HISTORY IN THE EVOLUTION OF DESIGN
(147) In the end, the qwerty keyboard was adopted throughout the world with but minor variations. We are committed to it, even though it was designed to satisfy constraints that no longer apply, was based on a style of typing no longer used, and is difficult to learn.
(150) Once a satisfactory product has been achieved, further change may be counterproductive, especially if the product is successful.
Why Designers Go Astray
(151) First, the reward structure of the design community tends to put aesthetics first. . . . Second, designers are not typical users. . . . Third, designers must please their clients, and the clients may not be the users.
PUTTING AESTHETICS FIRST
(151-152) Because prizes tend to be given for some aspects of a design, to the neglect of all others - usually including usability.
ARE NOT TYPICAL USERS
(156) In their work, designers often become expert with the device they are designing. Users are often expert at the task they are trying to perform with the device.
THE DESIGNER'S CLIENTS MAY NOT BE USERS
(157) The state of California requires by law that universities purchase things on a price basis; there are no legal requirements regarding understandability or usability of the product.
The Complexity of the Design Process
DESIGNING FOR SPECIAL PEOPLE
The handwriting example is great: the social convention of left to write scansion smudges.
(162) Some problems are not solved by adjustments. Left-handed
people, for example, present special problems.
(164) designing for flexibility helps.
SELECTIVE ATTENTION: THE PROBLEM OF FOCUS
(165) When there is a problem, people are apt to focus on it to the exclusion of other factors. The designer must design for the problem case, making other factors more salient, or easier to get to, or perhaps less necessary.
(165) A corollary principle is that designers must guard against the problems of focus in their own design.
The Faucet: A Case History of Design Difficulties
(170) If you can't put the knowledge on the device, then develop a cultural constraint: standardize what has to be kept in the head.
Two Deadly Temptations for the Designer
(173) Creeping featurism is the tendency to add to the number of features that a device can do, often extending the number beyond all reason.
(174) The proper division of a complex set of controls into modules allows you to conquer complexity.
THE WORSHIPPING OF FALSE IMAGES
(177) the false image is appearance of technical sophistication.
The Foibles of Computer Systems
Typical criticism of FOSS is lack of expertise designing for nonprofessionals to use.
(177) There is nothing particularly special about the computer; it is a machine, a human artifact, just like the other sorts of things we have looked at, and it poses few problems that we haven't encountered already. But designers of computer systems seem particularly oblivious to the needs of users, particularly susceptible to all the pitfalls of design. The professional design community is seldom called in to help with computer products. Instead, design is left in the hands of engineers and programmers, people who usually have no experience, and no expertise in designing for people.
HOW TO DO THINGS WRONG
(179) DO you want to do things wrong? Here is what to do: Make things invisible; Be arbitrary; Be inconsistent; Make operations unintelligible; Be impolite; Make operations dangerous.
IT'S NOT TOO LATE TO DO THINGS RIGHT
(180) the best computer programs are the ones in which the computer itself “disappears,” in which you work directly on the problem without having to be aware of the computer.
COMPUTER AS CHAMELEON
EXPLORABLE SYSTEMS: INVITING EXPERIMENTATION
(183) One important method of making systems easier to learn and to use is to make them explorable, to encourage the user to experiment and learn the possibilities through active exploration.
TWO MODES OF COMPUTER USAGE
Heim would argue strongly against this equivocating the computer as an ordinary tool; recommendation by Norman of designing software such that the computer disappears and the task is foregrounded allows concealing of enframing, recall Hegel worn sock is better than a mended one; not so with metaphysics.
(184) The point cannot be overstressed: make the computer system invisible. This principle can be applied with any form of system interaction, direct or indirect.
THE INVISIBLE COMPUTER OF THE FUTURE
Seven Principles for Transforming Difficult Tasks into Simple Ones
USE BOTH KNOWLEDGE IN THE WORLD AND KNOWLEDGE IN THE HEAD
THREE CONCEPTUAL MODELS
THE ROLE OF MANUALS
SIMPLIFY THE STRUCTURE OF TASKS
KEEP THE TASK MUCH THE AME, BUT PROVIDE MENTAL AIDS
USE TECHNOLOGY TO MAKE VISIBLE WHAT WOULD OTHERWISE BE INVISIBLE,
THUS IMPROVING FEEDBACK AND THE ABILITY TO KEEP CONTROL
(192) With modern computers and their powerful graphic displays, we now have the power to show what is really happening, to provide a good, complete image that matches the person's mental model of the task - thereby simplifying both understanding and performance.
(193) if the skill is easily automated, it wasn't essential.
(193) In general, I welcome any technological advance that reduces my need for mental work but still gives me the control and enjoyment of the task. . . . I want to use my mental powers for the important things, not fritter them away on the mechanics.
AUTOMATE, BUT KEEP THE TASK MUCH THE SAME
CHANGE THE NATURE OF THE TASK
(194) In general, technology can help transform deep, wide structures into narrower, shallower ones.
(194) The introduction of new fastening materials - for example, Velcro hook-and-loop fasteners - has eliminated the need for a complex sequence of skilled motor actions by changing the task to one this is considerably simpler, one that requires less skill.
Heim examines this shift in psychic framework in much more detail.
(195-196) Digital timepieces are controversial: in changing the
representation of time, the power of the analog form has been lost,
and it has become more difficult to make quick judgments about
(196) Today, because we can no longer remember the origins, we think of the analog system as necessary, virtuous, and proper. It presents a horrid, classic example of the mapping problem.
DON'T TAKE AWAY CONTROL
Supervisory control models, and closed-loop feedback.
(197) One problem is that overreliance on automated equipment can
eliminate a person's ability to function without it. . . . A second
problem is that a system may not always do things exactly the way we
would like, but we are forced to accept what happens because it is
too difficult (or impossible) to change the operation. A third
problem is that the person becomes a servant of the system, no longer
able to control or influence what is happening.
(197) All tasks have several layers of control. . . . Sometimes we really want to maintain control at the lower level. . . . At other times we want to concentrate on higher level things.
MAKE THINGS VISIBLE: BRIDGE THE GULFS OF EXECUTION AND EVALUATION
GET THE MAPPINGS RIGHT
(199) Natural mappings are the basis of what has been called “response compatibility” within the fields of human factors and ergonomics. . . . Difficulties arise wherever the positioning and movements of the controls deviate from strict proximity, mimicry, or analogy to the things being controlled.
EXPLOIT THE POWER OF CONSTRAINTS, BOTH NATURAL AND ARTIFICIAL
DESIGN FOR ERROR
WHEN ALL ELSE FAILS, STANDARDIZE
(201) standardization is essential only when all the necessary information cannot be placed in the world or when natural mappings cannot be exploited.
STANDARDIZATION AND TECHNOLOGY
(202) Standardization is simply another aspect of cultural constraints.
(202) Today's computers are still poorly designed, at least from the user's point of view. But on problem is simply that the technology is still very primitive - like the 1906 auto - and there is no standardization.
THE TIMING OF STANDARDIZATION
(202) Standardize and you simplify lives: everyone learns the system only once. But don't standardize too soon: you may be locked into a primitive technology, or you may have introduced rules that turn out to be grossly inefficient, even error-inducing. Standardize too late and there may already be so many ways of doing the task that no international standard can be agreed on; if there is agreement on an old-fashioned technology, it may be too expensive to change. The metric system is a good example.
Deliberately Making Things Difficult
DESIGNING A DUNGEONS AND DRAGONS GAME
(208) making things difficult is a tricky business. . . . several psychological factors hang in a delicate balance: challenge, enjoyment, frustration, and curiosity.
EASY LOOKING IS NOT NECESSARILY EASY TO USE
(209) Complexity of appearance seems to be determined by the number of controls, whereas difficulty of use is jointly determined by the difficulty of finding the relevant controls (which increases with the number of controls) and difficulty of executing the functions (which may decrease with the number of controls).
(209) Hide the controls not being used at the moment.
Design and Society
HOW WRITING METHOD AFFECTS STYLE
FROM QUILL AND INK TO KEYBOARD AND MICROPHONE
(211) Style may change further when we get voice typewriters, where our spoken words will appear on the page as they are spoken.
(211) On the one hand, it is satisfying to be able to type your thoughts without worrying about minor typographical errors or spelling. On the other hand, you may spend less time thinking and planning.
OUTLINE PROCESSORS AND HYPERTEXT
Reaches similar conclusions as Heim for outline processors and hypertext, but not at the same depth of ontological analysis.
(211) The current fad in writing aids is the outline processor, a
tool designed to encourage planning and reflection on the
organization of material. . . . Outline processors attempt to
overcome organizational problems by allowing collapsed views of the
manuscript to be examined and manipulated. But the process seems to
emphasize the organization that is visible in the outline or heading
structure of the manuscript, thereby deemphasizing other aspect of
the work. It is characteristic of thought processes that attention to
one aspect comes at the cost of decreased attention to others.
(212) Hypertext makes a virtue of lack of organization, allowing ideas and thoughts to be juxtaposed at will.
(212) Imagine that this book was in hypertext. How would it work? Well, I've used several devices that relate to hypertext: one is the footnote, another is parenthetical comments, and yet another is contrasting text.
(213) If hypertext really becomes available, especially in the fancy versions now being talked about - where words, sounds, video, computer graphics, simulations, and more are all available at the touch of the screen - well, it is hard to imagine anyone capable of preparing the material. It will take teams of people.
THE HOME OF THE FUTURE: A PLACE OF COMFORT OR A NEW SOURCE OF
(214) it is difficult to see how the complex instructions required for such a system will be conveyed.
The Design of Everyday Things
(216) Design, therefore, takes on political significance. . . . In Western cultures, design has reflected the capitalistic importance of the marketplace, with an emphasis on exterior features deemed to be attractive to the purchaser. . . . We are surrounded with objects of desire, not objects of use.
Feenberg tie-in to go along with the Heim tie-in: cry for usable products connects to democratic rationalization?
(216) If you are a designer, help fight the battle for usability. If you are a user, then join your voice with those who cry for usable products.
Norman, Donald A. (2002). The Design of Everyday Things. United States: Basic Books.
Norman, Donald A. The Design of Everyday Things. United States: Basic Books. 2002. Print.