Human–computer interaction - AbsoluteAstronomy.com

Human–computer Interaction (HCI) is the study, planning, and design of the interaction between people (user

User (computing)

A user is an agent, either a human agent or software agent, who uses a computer or network service. A user often has a user account and is identified by a username , screen name , nickname , or handle, which is derived from the identical Citizen's Band radio term.Users are...

s) and computers. It is often regarded as the intersection of computer science

Computer science

Computer science or computing science is the study of the theoretical foundations of information and computation and of practical techniques for their implementation and application in computer systems...

, behavioral sciences, design and several other fields of study. The term was coined by Card, Moran, and Newell in their book which gave birth to the field, "The Psychology of Human-Computer Interaction." The term carries the connotation that unlike other tools that only have one or a few affordances (such as a hammer, useful for driving nails, but not much else), a computer has many affordances for use and this takes place in a sort of open-ended dialog between the user and the computer.

Interaction between users and computers occurs at the user interface

User interface

The user interface, in the industrial design field of human–machine interaction, is the space where interaction between humans and machines occurs. The goal of interaction between a human and a machine at the user interface is effective operation and control of the machine, and feedback from the...

(or simply interface), which includes both software and hardware

Computer hardware

Personal computer hardware are component devices which are typically installed into or peripheral to a computer case to create a personal computer upon which system software is installed including a firmware interface such as a BIOS and an operating system which supports application software that...

; for example, characters or objects displayed by software on a personal computer's monitor, input received from users via hardware peripherals such as keyboards

Computer keyboard

In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches...

and mouses

Mouse (computing)

In computing, a mouse is a pointing device that functions by detecting two-dimensional motion relative to its supporting surface. Physically, a mouse consists of an object held under one of the user's hands, with one or more buttons...

, and other user interactions with large-scale computerized systems such as aircraft and power plants. The Association for Computing Machinery

Association for Computing Machinery

The Association for Computing Machinery is a learned society for computing. It was founded in 1947 as the world's first scientific and educational computing society. Its membership is more than 92,000 as of 2009...

defines human-computer interaction as "a discipline concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them." An often-sought facet of HCI is the securing of user satisfaction (see Computer user satisfaction

Computer user satisfaction

Computer user satisfaction is the attitude of a user to the computer system he employs in the context of his/her work environments...

), although user satisfaction is not the same thing as user performance by most meaningful metrics.

Because human-computer interaction studies a human and a machine in conjunction, it draws from supporting knowledge on both the machine and the human side. On the machine side, techniques in computer graphics

Computer graphics

Computer graphics are graphics created using computers and, more generally, the representation and manipulation of image data by a computer with help from specialized software and hardware....

, operating systems, programming language

Programming language

A programming language is an artificial language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine and/or to express algorithms precisely....

s, and development environments are relevant. On the human side, communication theory

Communication theory

Communication theory is a field of information and mathematics that studies the technical process of information and the human process of human communication.- History :- Origins :...

, graphic and industrial design disciplines, linguistics

Linguistics

Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....

, social sciences

Social sciences

Social science is the field of study concerned with society. "Social science" is commonly used as an umbrella term to refer to a plurality of fields outside of the natural sciences usually exclusive of the administrative or managerial sciences...

, cognitive psychology

Cognitive psychology

Cognitive psychology is a subdiscipline of psychology exploring internal mental processes.It is the study of how people perceive, remember, think, speak, and solve problems.Cognitive psychology differs from previous psychological approaches in two key ways....

, and human factors

Human factors

Human factors science or human factors technologies is a multidisciplinary field incorporating contributions from psychology, engineering, industrial design, statistics, operations research and anthropometry...

such as computer user satisfaction

Computer user satisfaction

Computer user satisfaction is the attitude of a user to the computer system he employs in the context of his/her work environments...

are relevant. Engineering and design methods are also relevant. Due to the multidisciplinary nature of HCI, people with different backgrounds contribute to its success. HCI is also sometimes referred to as man–machine interaction (MMI) or computer–human interaction (CHI).

Attention to human-machine interaction is important, because poorly designed human-machine interfaces can lead to many unexpected problems. A classic example of this is the Three Mile Island accident

Three Mile Island accident

The Three Mile Island accident was a core meltdown in Unit 2 of the Three Mile Island Nuclear Generating Station in Dauphin County, Pennsylvania near Harrisburg, United States in 1979....

where investigations concluded that the design of the human-machine interface was at least partially responsible for the disaster. Similarly, accidents in aviation have resulted from manufacturers' decisions to use non-standard flight instrument and/or throttle

Throttle

A throttle is the mechanism by which the flow of a fluid is managed by constriction or obstruction. An engine's power can be increased or decreased by the restriction of inlet gases , but usually decreased. The term throttle has come to refer, informally and incorrectly, to any mechanism by which...

quadrant layouts: even though the new designs were proposed to be superior in regards to basic human-machine interaction, pilots had already ingrained the "standard" layout and thus the conceptually good idea actually had undesirable results.

Goals

A basic goal of HCI is to improve the interactions between users and computers by making computers more usable

USable

USable is a special idea contest to transfer US American ideas into practice in Germany. USable is initiated by the German Körber-Stiftung .It is doted with 150,000 Euro and awarded every two years. All persons which know Germany and the USA from their own experience can take part in the contest...

and receptive to the user's needs. Specifically, HCI is concerned with:

methodologies and processes for designing interfaces (i.e., given a task and a class of users, design the best possible interface within given constraints, optimizing for a desired property such as learnability or efficiency of use)
methods for implementing interfaces (e.g. software toolkits and libraries
Library (computer science)
In computer science, a library is a collection of resources used to develop software. These may include pre-written code and subroutines, classes, values or type specifications....

; efficient algorithm
Algorithm
In mathematics and computer science, an algorithm is an effective method expressed as a finite list of well-defined instructions for calculating a function. Algorithms are used for calculation, data processing, and automated reasoning...

s)
techniques for evaluating and comparing interfaces
developing new interfaces and interaction techniques
developing descriptive and predictive models and theories of interaction

A long term goal of HCI is to design systems that minimize the barrier between the human's cognitive model of what they want to accomplish and the computer's understanding of the user's task.

Professional practitioners in HCI are usually designers concerned with the practical application of design methodologies to real-world problems. Their work often revolves around designing graphical user interface

Graphical user interface

In computing, a graphical user interface is a type of user interface that allows users to interact with electronic devices with images rather than text commands. GUIs can be used in computers, hand-held devices such as MP3 players, portable media players or gaming devices, household appliances and...

s and web interfaces

Web design

Web design is the process of planning and creating a website. Text, images, digital media and interactive elements are used by web designers to produce the page seen on the web browser...

.

Researchers in HCI are interested in developing new design methodologies, experimenting with new hardware devices, prototyping new software systems, exploring new paradigms for interaction, and developing models and theories of interaction.

Differences with related fields

HCI differs from human factors

Human factors

(or ergonomics

Ergonomics

Ergonomics is the study of designing equipment and devices that fit the human body, its movements, and its cognitive abilities.The International Ergonomics Association defines ergonomics as follows:...

) in that with HCI the focus is more on users working specifically with computers, rather than other kinds of machines or designed artifacts. There is also a focus in HCI on how to implement the computer software and hardware mechanisms to support human-computer interaction. Thus, human factors

Human factors

is a broader term; HCI could be described as the human factors of computers – although some experts try to differentiate these areas.

HCI also differs from human factors

Human factors

in that there is less of a focus on repetitive work-oriented tasks and procedures, and much less emphasis on physical stress and the physical form or industrial design

Industrial design

Industrial design is the use of a combination of applied art and applied science to improve the aesthetics, ergonomics, and usability of a product, but it may also be used to improve the product's marketability and production...

of the user interface, such as keyboards

Computer keyboard

In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches...

and mouse devices

Mouse (computing)

.

Three areas of study have substantial overlap with HCI even as the focus of inquiry shifts. In the study of personal information management

Personal information management

Personal information management refers to the practice and the study of the activities people perform in order to acquire, organize, maintain, retrieve and use information items such as documents , web pages and email messages for everyday use to complete tasks and fulfill a person’s various...

(PIM), human interactions with the computer are placed in a larger informational context – people may work with many forms of information, some computer-based, many not (e.g., whiteboards, notebooks, sticky notes, refrigerator magnets) in order to understand and effect desired changes in their world. In computer supported cooperative work

Computer supported cooperative work

The term computer-supported cooperative work was first coined by Irene Greif and Paul M. Cashman in 1984, at a workshop attended by individuals interested in using technology to support people in their work. At about this same time, in 1987 Dr...

(CSCW), emphasis is placed on the use of computing systems in support of the collaborative work of a group of people. The principles of human interaction management

Human interaction management

Human Interaction Management is a set of management principles, patterns and techniques complementary to Business process management...

(HIM) extend the scope of CSCW to an organizational level and can be implemented without use of computer systems.

Design principles

When evaluating a current user interface

User interface

, or designing a new user interface, it is important to keep in mind the following experimental design principles:

Early focus on user(s) and task(s): Establish how many users are needed to perform the task(s) and determine who the appropriate users should be; someone who has never used the interface, and will not use the interface in the future, is most likely not a valid user. In addition, define the task(s) the users will be performing and how often the task(s) need to be performed.
Empirical
Empirical
The word empirical denotes information gained by means of observation or experimentation. Empirical data are data produced by an experiment or observation....

measurement: Test the interface early on with real users who come in contact with the interface on an everyday basis. Keep in mind that results may be altered if the performance level of the user is not an accurate depiction of the real human-computer interaction. Establish quantitative usability specifics such as: the number of users performing the task(s), the time to complete the task(s), and the number of errors made during the task(s).
Iterative design
Iterative design
Iterative design is a design methodology based on a cyclic process of prototyping, testing, analyzing, and refining a product or process. Based on the results of testing the most recent iteration of a design, changes and refinements are made. This process is intended to ultimately improve the...

: After determining the users, tasks, and empirical measurements to include, perform the following iterative design steps:

Design the user interface
Test
Analyze results
Repeat

Repeat the iterative design process until a sensible, user-friendly interface is created.

Design methodologies

A number of diverse methodologies outlining techniques for human–computer interaction design have emerged since the rise of the field in the 1980s. Most design methodologies stem from a model for how users, designers, and technical systems interact. Early methodologies, for example, treated users' cognitive processes as predictable and quantifiable and encouraged design practitioners to look to cognitive science results in areas such as memory and attention when designing user interfaces. Modern models tend to focus on a constant feedback and conversation between users, designers, and engineers and push for technical systems to be wrapped around the types of experiences users want to have, rather than wrapping user experience around a completed system.

User-centered design
User-centered design
In broad terms, user-centered design or pervasive usability is a design philosophy and a process in which the needs, wants, and limitations of end users of a product are given extensive attention at each stage of the design process...

: user-centered design (UCD) is a modern, widely practiced design philosophy rooted in the idea that users must take center-stage in the design of any computer system. Users, designers and technical practitioners work together to articulate the wants, needs and limitations of the user and create a system that addresses these elements. Often, user-centered design projects are informed by ethnographic
Ethnography
Ethnography is a qualitative method aimed to learn and understand cultural phenomena which reflect the knowledge and system of meanings guiding the life of a cultural group...

studies of the environments in which users will be interacting with the system. This practice is similar but not identical to Participatory Design
Participatory design
Participatory design is an approach to design attempting to actively involve all stakeholders in the design process in order to help ensure the product designed meets their needs and is usable. The term is used in a variety of fields e.g...

, which emphasizes the possibility for end-users to contribute actively through shared design sessions and workshops.

Principles of User Interface Design
Principles of User Interface Design
The principles of user interface design are intended to improve the quality of user interface design. According to Larry Constantine and Lucy Lockwood in their usage-centered design, these principles are:...

: these are seven principles that may be considered at any time during the design of a user interface in any order, namely Tolerance, Simplicity, Visibility, Affordance, Consistency, Structure and Feedback.

See List of human-computer interaction topics#Interface design methods for more

Display designs

Displays are human-made artifacts designed to support the perception of relevant system variables and to facilitate further processing of that information. Before a display is designed, the task that the display is intended to support must be defined (e.g. navigating, controlling, decision making, learning, entertaining, etc.). A user or operator must be able to process whatever information that a system generates and displays; therefore, the information must be displayed according to principles in a manner that will support perception, situation awareness, and understanding.

Thirteen principles of display design

Christopher Wickens et al. defined 13 principles of display design in their book An Introduction to Human Factors Engineering.

These principles of human perception and information processing can be utilized to create an effective display design. A reduction in errors, a reduction in required training time, an increase in efficiency, and an increase in user satisfaction are a few of the many potential benefits that can be achieved through utilization of these principles.

Certain principles may not be applicable to different displays or situations. Some principles may seem to be conflicting, and there is no simple solution to say that one principle is more important than another. The principles may be tailored to a specific design or situation. Striking a functional balance among the principles is critical for an effective design.

Perceptual principles

1. Make displays legible (or audible). A display’s legibility is critical and necessary for designing a usable display. If the characters or objects being displayed cannot be discernible, then the operator cannot effectively make use of them.

2. Avoid absolute judgment limits. Do not ask the user to determine the level of a variable on the basis of a single sensory variable (e.g. color, size, loudness). These sensory variables can contain many possible levels.

3. Top-down processing. Signals are likely perceived and interpreted in accordance with what is expected based on a user’s past experience. If a signal is presented contrary to the user’s expectation, more physical evidence of that signal may need to be presented to assure that it is understood correctly.

4. Redundancy gain. If a signal is presented more than once, it is more likely that it will be understood correctly. This can be done by presenting the signal in alternative physical forms (e.g. color and shape, voice and print, etc.), as redundancy does not imply repetition. A traffic light is a good example of redundancy, as color and position are redundant.

5. Similarity causes confusion: Use discriminable elements. Signals that appear to be similar will likely be confused. The ratio of similar features to different features causes signals to be similar. For example, A423B9 is more similar to A423B8 than 92 is to 93. Unnecessary similar features should be removed and dissimilar features should be highlighted.

Mental model principles

6. Principle of pictorial realism. A display should look like the variable that it represents (e.g. high temperature on a thermometer shown as a higher vertical level). If there are multiple elements, they can be configured in a manner that looks like it would in the represented environment.

7. Principle of the moving part. Moving elements should move in a pattern and direction compatible with the user’s mental model of how it actually moves in the system. For example, the moving element on an altimeter should move upward with increasing altitude.

Principles based on attention

8. Minimizing information access cost. When the user’s attention is diverted from one location to another to access necessary information, there is an associated cost in time or effort. A display design should minimize this cost by allowing for frequently accessed sources to be located at the nearest possible position. However, adequate legibility should not be sacrificed to reduce this cost.

9. Proximity compatibility principle. Divided attention between two information sources may be necessary for the completion of one task. These sources must be mentally integrated and are defined to have close mental proximity. Information access costs should be low, which can be achieved in many ways (e.g. proximity, linkage by common colors, patterns, shapes, etc.). However, close display proximity can be harmful by causing too much clutter.

10. Principle of multiple resources. A user can more easily process information across different resources. For example, visual and auditory information can be presented simultaneously rather than presenting all visual or all auditory information.

Memory principles

11. Replace memory with visual information: knowledge in the world. A user should not need to retain important information solely in working memory or to retrieve it from long-term memory. A menu, checklist, or another display can aid the user by easing the use of their memory. However, the use of memory may sometimes benefit the user by eliminating the need to reference some type of knowledge in the world (e.g. an expert computer operator would rather use direct commands from memory than refer to a manual). The use of knowledge in a user’s head and knowledge in the world must be balanced for an effective design.

12. Principle of predictive aiding. Proactive actions are usually more effective than reactive actions. A display should attempt to eliminate resource-demanding cognitive tasks and replace them with simpler perceptual tasks to reduce the use of the user’s mental resources. This will allow the user to not only focus on current conditions, but also think about possible future conditions. An example of a predictive aid is a road sign displaying the distance from a certain destination.

13. Principle of consistency. Old habits from other displays will easily transfer to support processing of new displays if they are designed in a consistent manner. A user’s long-term memory will trigger actions that are expected to be appropriate. A design must accept this fact and utilize consistency among different displays.

Human–computer interface

The human–computer interface can be described as the point of communication between the human user and the computer. The flow of information between the human and computer is defined as the loop of interaction. The loop of interaction has several aspects to it including:

Task Environment: The conditions and goals set upon the user.
Machine Environment: The environment that the computer is connected to, i.e. a laptop in a college student's dorm room.
Areas of the Interface: Non-overlapping areas involve processes of the human and computer not pertaining to their interaction. Meanwhile, the overlapping areas only concern themselves with the processes pertaining to their interaction.
Input Flow: The flow of information that begins in the task environment, when the user has some task that requires using their computer.
Output: The flow of information that originates in the machine environment.
Feedback: Loops through the interface that evaluate, moderate, and confirm processes as they pass from the human through the interface to the computer and back.

User customisation

End-user development studies how ordinary users could routinely tailor applications to their own needs and use this power to invent new applications based on their understanding of their own domains. Users, with their deeper knowledge of their own knowledge domains, could increasingly be important sources of new applications at the expense of generic systems programmers (with systems expertise but low domain expertise).

Embedded computation

Computation is passing beyond desktop computers into every object for which uses can be found. Embedded systems make the environment alive with little computations and automated processes, from computerized cooking appliances to lighting and plumbing fixtures to window blinds to automobile braking systems to greeting cards. To some extent, this development is already taking place. The expected difference in the future is the addition of networked communications that will allow many of these embedded computations to coordinate with each other and with the user. Human interfaces to these embedded devices will in many cases be very different from those appropriate to workstations.

Augmented reality

A common staple of science fiction, augmented reality refers to the notion of layering relevant information into our vision of the world. Existing projects show real-time statistics to users performing difficult tasks, such as manufacturing. Future work might include augmenting our social interactions by providing additional information about those we converse with.

Factors of change

The means by which humans interact with computers continues to evolve rapidly. Human–computer interaction is affected by the forces shaping the nature of future computing. These forces include:

Decreasing hardware costs leading to larger memory and faster systems
Miniaturization of hardware leading to portability
Reduction in power requirements leading to portability
New display technologies leading to the packaging of computational devices in new forms
Specialized hardware leading to new functions
Increased development of network communication and distributed computing
Increasingly widespread use of computers, especially by people who are outside of the computing profession
Increasing innovation in input techniques (i.e., voice, gesture
Gesture recognition
Gesture recognition is a topic in computer science and language technology with the goal of interpreting human gestures via mathematical algorithms. Gestures can originate from any bodily motion or state but commonly originate from the face or hand. Current focuses in the field include emotion...

, pen), combined with lowering cost, leading to rapid computerization by people previously left out of the "computer revolution."
Wider social concerns leading to improved access to computers by currently disadvantaged groups

The future for HCI, based on current promising research, is expected to include the following characteristics:

Ubiquitous communication
Ubiquitous computing
Ubiquitous computing is a post-desktop model of human-computer interaction in which information processing has been thoroughly integrated into everyday objects and activities. In the course of ordinary activities, someone "using" ubiquitous computing engages many computational devices and systems...

. Computers are expected to communicate through high speed local networks, nationally over wide-area networks, and portably via infrared, ultrasonic, cellular, and other technologies. Data and computational services will be portably accessible from many if not most locations to which a user travels.

High functionality systems. Systems can have large numbers of functions associated with them. There are so many systems that most users, technical or non-technical, do not have time to learn them in the traditional way (e.g., through thick manuals).

Mass availability of computer graphics. Computer graphics capabilities such as image processing, graphics transformations, rendering, and interactive animation are becoming widespread as inexpensive chips become available for inclusion in general workstations and mobile devices.

Mixed media. Commercial systems can handle images, voice, sounds, video, text, formatted data. These are exchangeable over communication links among users. The separate worlds of consumer electronics (e.g., stereo sets, VCRs, televisions) and computers are partially merging. Computer and print worlds are expected to cross-assimilate each other.

High-bandwidth interaction. The rate at which humans and machines interact is expected to increase substantially due to the changes in speed, computer graphics, new media, and new input/output devices. This can lead to some qualitatively different interfaces, such as virtual reality
Virtual reality
Virtual reality , also known as virtuality, is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds...

or computational video.

Large and thin displays. New display technologies are finally maturing, enabling very large displays and displays that are thin, lightweight, and low in power consumption. This is having large effects on portability and will likely enable the development of paper-like, pen-based computer interaction systems very different in feel from desktop workstations of the present.

Information Utilities. Public information utilities (such as home banking and shopping) and specialized industry services (e.g., weather for pilots) are expected to proliferate. The rate of proliferation can accelerate with the introduction of high-bandwidth interaction and the improvement in quality of interfaces.

Academic conferences

One of the top academic conferences for new research in human-computer interaction, especially within computer science

Computer science

, is the annually held ACM

Association for Computing Machinery

's Conference on Human Factors in Computing Systems

CHI (conference)

The ACM Conference on Human Factors in Computing Systems series of academic conferences is generally considered the most prestigious in the field of human–computer interaction. It is hosted by ACM SIGCHI, the Special Interest Group on computer–human interaction. CHI has been held annually since...

, usually referred to by its short name CHI . CHI is organized by ACM SIGCHI Special Interest Group on Computer–Human Interaction. CHI is a large, highly competitive conference, with thousands of attendants, and is quite broad in scope.

There are also dozens of other smaller, regional or specialized HCI-related conferences held around the world each year, the most important of which include (see also http://www.confsearch.org/confsearch/faces/pages/topic.jsp?topic=hci&sortMode=1&graphicView=true):

Special purpose

ASSETS: ACM International Conference on Computers and Accessibility
CSCW: ACM conference on Computer Supported Cooperative Work
Computer supported cooperative work
The term computer-supported cooperative work was first coined by Irene Greif and Paul M. Cashman in 1984, at a workshop attended by individuals interested in using technology to support people in their work. At about this same time, in 1987 Dr...

.
DIS: ACM conference on Designing Interactive Systems.
ECSCW: European Conference on Computer-Supported Cooperative Work. Every second year.
GROUP: ACM conference on supporting Group work
Group work
Group work a form of cooperative learning. It aims to cater for individual differences, develop students' knowledge, generic skills and attitudes....

.
HRI: ACM/IEEE International Conference on Human-robot interaction.
ICMI: International Conference on Multimodal Interfaces.
ITS: ACM conference on Interactive Tabletops and Surfaces.
IUI: International Conference on Intelligent User Interfaces.
MobileHCI: International Conference on Human-Computer Interaction with Mobile Devices and Services.
NIME: International Conference on New Interfaces for Musical Expression
New Interfaces for Musical Expression
New Interfaces for Musical Expression, also known as NIME, is an international conference dedicated to scientific research on the development of new technologies for musical expression and artistic performance...

.
Ubicomp: International Conference on Ubiquitous computing
Ubiquitous computing
Ubiquitous computing is a post-desktop model of human-computer interaction in which information processing has been thoroughly integrated into everyday objects and activities. In the course of ordinary activities, someone "using" ubiquitous computing engages many computational devices and systems...
UIST: ACM Symposium on User Interface Software and Technology.
i-USEr: International Conference on User Science and Engineering

External links

HCI Review
Bad Human Factors Designs
The HCI Wiki Bibliography with over 100,000 publications.
The HCI Bibliography Over 58,000 publications about HCI.
Human-Centered Computing Education Digital Library
Usability Views
HCI Webliography with a list of about 100 HCI Organizations worldwide

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

Goals

Differences with related fields

Design principles

Design methodologies

Display designs

Thirteen principles of display design

Perceptual principles

Mental model principles

Principles based on attention

Memory principles

Human–computer interface

User customisation

Embedded computation

Augmented reality

Factors of change

Academic conferences

Special purpose

See also

Further reading

External links