Exploring the HumanComputer Interface

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WHAT THE DIGERATI KNOW
chapter2

• Exploring the Human-Computer Interface

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HCI

• Definition of HCI
• Human-computer interaction is 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.
• (SIGCHI / ACM _at_ http//sigchi.org/cdg/cdg2.html)

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HCI

• HCI concerns study of the human AND the computer
• Human factors is concerned only with the human
• Many people think HCI is only concerned with
  design of a GUI (Graphical User Interface)
• HCI is an interdisciplinary field

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HCI

• Computer Science
• Application design
• GUI design
• Psychology
• Theory of human cognition
• User behavior
• Sociology/Anthropology
• Social cultural interactions between people,
  organizations and society at large

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HCI

• Industrial design
• Design of interactive products for ease of use
  (ergonomics)
• For example, the psychological aspect includes
  theories on
• Human cognition, memory, perception, motor
  skills, attention vigilance, problem solving,
  learning motivation
• Human diversity, accessibility

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HCI

• Key impacts of HCI study and analysis
• Good vs. bad GUI design
• How diverse users interact with systems
• Variable skill levels, habits, cultural norms
• Need to collaborate with other specialists in HCI
• No one can know it all
• Must integrate into system analysis design
• HCI just as important as internal system code

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GUI - Form Follows Function

• A task determines most aspects of software
• Different vendor software for an application,
  like browsing or word processing, have
• Different look and feel
• Similar operations, similar behaviors, similar
  tools
• They are more alike than different

If you know one, you can figure out the other
easily
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Consequences of Form Follows Function

• Because the task determines the software
• A new software version will have most of the
  features of the last version -- youll learn it
  fast
• When using some other computer with another
  vendors software, expect it to be similar to
  your own

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Graphical user interface for one version of an
Apple Macintosh audio CD player.
What features look familiar?
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Audio CD player GUI for the Windows operating
system
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Audio CD GUI displaying hidden titles and track
info
What cues might suggest the track list can be
edited?
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Customized Audio CD player GUI
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Standard File and Edit menus
Keyboard shortcuts are your friend! Use them!
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An insert menu showing ellipses and triangle
pointer
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Bad GUI Design

• By now, you might think all commercial SW offer
  good GUIs.not so!
• The Interface Hall of Shame has plenty of
  examples

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A New monthly calendar showing a blank
instance.
New creates a blank instance
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Examples of selection.
Selecting red and green requires shift select
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Searching occurs in many contexts

• Searching (Find) has a standard operation
• look for exact match, starting at current
  position
• look for tokens -- usually letters
• Watch for
• case sensitivity rights ? Rights
• hidden text, e.g. unprintable formatting
  characters
• substrings matches rather than whole words

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The Placeholder Technique

• The placeholder technique uses find/replace to
  clean up text
• The three steps
• Mark the positions of all strings that conflict
  using a placeholder, i.e. any unique string such
  as
• Remove the offending strings
• Replace the placeholders with the original strings

Mississipspsi -- unnecessary ss Miiipspsi --
mark ss with Miiippi -- remove unnecessary
ss Mississippi -- restore ss