Lecture Overview

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Lecture Overview

• Definition of HCI User Interface
• Approach of HCI - User-Centred
• Trace the Evolution of HCI/GUI development
• Rise in Usability issues
• Consequences of poor HCI
• Benefits of good HCI
• Interdisciplinary Nature of HCI

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Definition of HCI

• According to Preece (1994), the term
  Human-Computer Interaction was adopted in the
  mid-1980s.
• It describe an emerging field that concerned
  itself with the human (user) aspects of
  information systems (IS) development.
• There is no single accepted definition of what
  exactly constitutes HCI.

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Definition of HCI

• A set of processes, dialogues, and actions
  through which a human user employs and interacts
  with a computer
• (Baecker and Buxton, 1987)
• Human-computer interaction is a discipline
  concerned with the design, evaluation and
  implementation of interactive computing systems
  for human use.
• (ACM SIGCHI, 19926)

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Definition of HCI

• The User Interface may be defined thus
  
• Those visual and operational techniques that
  facilitate the interaction between the human user
  and a computer system application

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HCI Approach User-Centred

• HCI is NOT just about designing pretty
  interfaces.
• The central aim of HCI is to optimise performance
  of human and computer together as a system.

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HCI Approach User-Centred

• It is a design philosophy that explicitly
  incorporates a User-Centred perspective.
• The approach is User-Centred because it
  explicitly acknowledges the importance of
  adopting a User-focused (as opposed to a
  System-focused) perspective.

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Evolution of HCI/GUI Development

• In the past - emphasis in programming was on
  Functionality getting programs to work as
  efficiently as possible (or even just to work!).
• Little consideration given to the actions
  required from humans who wish to make use of that
  functionality

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Evolution of HCI/GUI Development

• Computer Systems have changed over time. In
• 1950s Research Machines for scientists/
  mathematicians. Very specific use.
• 1960s/70s Mainframes Data processing
  professionals.
• 1970s Minicomputers Engineering and other
  specialist non-computer professionals.

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Evolution of HCI/GUI Development

• 1980s Microcomputers. Almost anyone.
• Thus from the 1980s onwards HCI became important
  vast numbers of new non computer specialist
  users, interacted with computer screens and
  dialogue.

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Consequences of Poor HCI

• In general, the following have been shown to
  result from poor interface design
• Increased mistakes in data entry and system
  operation.
• Inaccessible functionality.
• User frustration low productivity and/or under
  utilisation.
• System failure because of user rejection.
• To avoid these shortcomings it is estimated that
  nowadays nearly a half of software development
  effort relates to the user interface.

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Consequences of Poor HCI

• Three Mile Island nuclear power plant meltdown
  in 1979 - attributed to poor control panel and
  alarm system design. Hundreds of alarms and
  warnings going off simultaneously.
• London ambulance system - drivers and operators
  kept pushing wrong buttons, leading to eventual
  system overload and breakdown. System abandoned
  after a few days.

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Benefits of Good HCI Design

• User completes tasks faster (Higher Productivity)
• Lower frustration
• Perceived lower fatigue
• Better able to self-teach - reduced training
  costs
• Better able to learn more capabilities of
  applications

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Inter-disciplinary nature of HCI

• HCI involves more than simply designing pretty
  interfaces
• Designers must draw on knowledge from a whole
  range of disciplines in an effort to understand
• Users Users Work
• Work Environment Technology

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Inter-disciplinary nature of HCI
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Computer Science

• Knowledge about the capabilities of the
  technology (Hardware and Software).
• Especially how this might be harnessed in the
  development of good user interfaces.

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Cognitive Psychology

• Understanding human behaviour and the mental
  processes that drive humans
• Viewing the brain as an information processing
  device.
• Knowledge about perception, memory, learning,
  thinking and problem-solving.

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Social and Organisational Psychology/Sociology

• Concerned with studying the nature and causes of
  human behaviour in social contexts i.e. groups.
• impact of a group on its members attitudes and
  behaviour.
• impact of a member on a groups activities and
  structure

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Ergonomics

• How to make tasks easier to perform, and increase
  feelings of comfort and satisfaction.
• Deals with factors such as keyboard, mouse,
  seating design readability of computer screens
  avoidance of injury (eg RSI).

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Graphic Design

• This is primarily concerned with the
  communicative aspects of designing. It includes
  unique appreciation of fonts, typestyles,
  colours, etc.
• Contributions can range from the design of icons,
  screen layouts, menu formats to the strategic
  design of an overall system.

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Artificial Intelligence

• AI knowledge and methods can be applied to the
  design of intelligent user interfaces.
• For example, the use of Natural Language and
  Speech when interacting with the computer

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Week One Lecture Review

• Definition of HCI User Interface
• Approach of HCI - User-Centred
• Trace the Evolution of HCI/GUI development
• Rise in Usability issues
• Consequences of poor HCI - Examples
• Benefits of good HCI
• Interdisciplinary Nature of HCI