its oresentationhdafkefadchksdbv

1. paradigms
Lecture 7

2. Today’s Outline
 Topics of discussion included today are,
 Paradigms, interaction and Example
 Time Sharing
 Video Display Units
 Programming Toolkits
 Window systems and the WIMP interface
 Metaphor
 Direct manipulation
 Language versus Action
 Modern evolving paradigms of computing

3. Introduction to Paradigm
 The primary objective of an interactive system is
to allow the user to achieve particular goals in
some application domain, that is, the interactive
system must be usable.

4. Introduction to Paradigm
 The designer of an interactive system, then, is
posed with two open questions:
1. How can an interactive system be developed to
ensure its usability?
2. How can the usability of an interactive system be
demonstrated or measured?

5. Paradigms
 One approach to answering these questions is by
means of example, in which successful interactive
systems are commonly believed to enhance
usability and, therefore, serve as paradigms for
the development of future products.

6. What are Paradigms
 Predominant theoretical frameworks or scientific world
views
 e.g., Aristotelian, Newtonian, Einsteinian (relativistic)
paradigms in physics
 Understanding HCI history is largely about
understanding a series of paradigm shifts
 Not all listed here are necessarily “paradigm” shifts, but are at
least candidates
 History will judge which are true shifts

7. A paradigm is a way of thinking about
the world.

8. Paradigms of interaction
New computing technologies arrive,
creating a new perception of the
human—computer relationship.
We can trace some of these shifts in
the history of interactive technologies.

9. The initial paradigm
 Batch processing
Impersonal computing

10. Batch processing

11. Example Paradigm Shifts
 Batch processing
 Time-sharing
Interactive computing

12. Example Paradigm Shifts
 Batch processing
 Timesharing
 Networking
???
@#$% !
Community computing

13. Example Paradigm Shifts
 Batch processing
 Timesharing
 Networking
 Graphical displays % foo.bar
ABORT
dumby!!!
C…P… filename
dot star… or was
it R…M?
Move this file here,
and copy this to there.
Direct manipulation

14. Example Paradigm Shifts
 Batch processing
 Timesharing
 Networking
 Graphical display
 Microprocessor
Personal computing

15. Example Paradigm Shifts
 Batch processing
 Timesharing
 Networking
 Graphical display
 Microprocessor
 WWW
Global information

16. Example Paradigm Shifts
 A symbiosis of physical and
electronic worlds in service of
everyday activities.
• Batch processing
• Timesharing
• Networking
• Graphical display
• Microprocessor
• WWW
• Ubiquitous
Computing

17. Ubiquitous Computing

18. Time-sharing
 In the 1940s and 1950s, the significant advances in
computing consisted of new hardware technologies.
 Mechanical relays were replaced by vacuum electron tubes.
Tubes were replaced by transistors, and transistors by
integrated chips, all of which meant that the amount of sheer
computing power was increasing by orders of magnitude.
 By the 1960s it was becoming apparent that the
explosion of growth in computing power would be
wasted if there was not an equivalent explosion of
ideas about how to channel that power.

19. Time Sharing
 A new concept of time sharing is introduced.
 a single computer could support multiple users.
 Previously, the programmer was restricted to
batch sessions, in which complete jobs were
submitted on punched cards or paper tape to
an operator who would then run them
individually on the computer.

20. Time Sharing
 Time-sharing systems of the 1960s made
programming a truly interactive venture and
brought about a subculture of programmers
known as ‘hackers’
 i.e.; single-minded masters of detail who took
pleasure in understanding complexity.
 Now with time-sharing capability, true human
computer interaction is possible.

21. Video Display Units
 As early as the mid-1950s researchers were
experimenting with the possibility of presenting and
manipulating information from a computer in the form
of images on a video display unit (VDU).
 These display screens could provide a more suitable
medium than a paper printout for presenting vast
quantities of strategic information for rapid
assimilation.
 The earliest applications of display screen images
were
 developed in military applications, most notably the
Semi-Automatic Ground Environment (SAGE) project
of the US Air Force.

22. Visual Display units
 Primary user hardware for displaying visual
media such as graphics, text, images.
 Consists of components such as Monitor,
Video adapter card, video adapter cable.
 Various such devices are CRT, color CRT,
DVST, Flat Panel Displays (LCD & Plasma),
LED monitors, etc.

23. Old monochrome vs Lcd

24. Video Display Units
 In1962, a young graduate student at the
Massachusetts Institute of Technology (MIT), Ivan
Sutherland, astonished the established computer
science community with his Sketch pad program,
that the capabilities of visual images were
realized.

25. Sketch pad Program

26. Video Display Unit
 Sketchpad demonstrated two important ideas.
 First, computers could be used for more than just
data processing.
 Secondly, Sutherland’s efforts demonstrated how
important the contribution of one creative mind

27. Programming Toolkits
 Douglas Engelbart’s ambition since the early
1950s was to use computer technology as a
means of complementing human problem solving
activity.
 Engelbart’s idea as a graduate student at the
University of California at Berkeley was to use the
computer to teach humans.

28. Douglas Engelbart’s ambition
“By ‘augmenting man’s intellect’ we mean
increasing the capability of a man to approach
a complex problem situation, gain
comprehension to suit his particular needs,
and to derive solutions to problems.... We
refer to a way of life in an integrated domain
where hunches, cut-and-try, intangibles, and
the human ‘feel for the situation’ usefully
coexist with powerful concepts, streamlined
terminology and notation, sophisticated
methods, and high-powered electronic aids”.

29. Programming Toolkits
 Ideas that Engelbart’s team developed at the
Augmentation Research Center includes
 word processing and
 the mouse

30. Programming toolkits in Overview
 Engelbart at Stanford Research Institute
 1963 – augmenting man's intellect
 1968 NLS/Augment system demonstration
 the right programming toolkit provides building blocks
to producing complex interactive systems

31. Personal computing
 1970s – Papert's LOGO
language for simple graphics
programming by children
 A system is more powerful as
it becomes easier to user
 Future of computing in small,
powerful machines dedicated
to the individual
 Kay at Xerox PARC – the
Dynabook as the ultimate
personal computer

32. Window systems and the WIMP
interface
 humans can pursue more
than one task at a time
 windows used for dialogue
partitioning, to “change the
topic”
 1981 – Xerox Star first
commercial windowing
system
 windows, icons, menus and
pointers now familiar
interaction mechanisms

33. Metaphor
 relating computing to other real-world
activity is effective teaching technique
 LOGO's turtle dragging its tail
 file management on an office desktop
 word processing as typing
 financial analysis on spreadsheets
 virtual reality – user inside the metaphor
 Problems
 some tasks do not fit into a given metaphor
 cultural bias

34. Metaphore
 In developing the LOGO language to teach
children, Papert used the metaphor of a turtle
dragging its tail in the dirt.
 Children could quickly identify with the real-world
phenomenon and that instant familiarity gave them
an understanding of how they could create pictures.

35. Metaphor
 Metaphors are used quite successfully to teach
new concepts in terms of ones which are already
understood.
 Metaphors are used to describe the functionality of
many interaction widgets, such as windows, menus,
buttons and palettes.

36. Direct Manipulation
 In the early 1980s as the price of fast and high-
quality graphics hardware was steadily
decreasing, designers were beginning to see that
their products were gaining popularity as their
visual content increased.

37. Direct Manipulation
 As long as the user–system dialog remained
largely unidirectional – from user command to
system command line prompt computing was
going to stay within the minority population of
the hackers (programmers) who reveled in the
challenge of complexity.
 In a standard command line interface, the only way
to get any feedback on the results of previous
interaction is to know that you have to ask for it and
to know how to ask for it.

38. Direct Manipulation
 Rapid feedback is just one feature of the
interaction technique known as direct
manipulation.

39. Direct Manipulation
 Ben Shneiderman highlights the following features of
a direct manipulation interface:
 visibility of the objects of interest
 incremental action at the interface with rapid feedback on all
actions
 reversibility of all actions, so that users are encouraged to
explore without severe penalties
 syntactic correctness of all actions, so that every user action is
a legal operation
 replacement of complex command languages with actions to
manipulate directly
 the visible objects (and, hence, the name direct manipulation)

40. Direct Manipulation
 The first real commercial success which
demonstrated the inherent usability of direct
manipulation interfaces for the general public was
the Macintosh personal computer, introduced by
Apple Computer, Inc. in 1984

41. Direct manipulation – in overview
 1982 – Shneiderman describes appeal of graphically-
based interaction
 visibility of objects
 incremental action and rapid feedback
 reversibility encourages exploration
 syntactic correctness of all actions
 replace language with action
 1984 – Apple Macintosh
 the model-world metaphor
 What You See Is What You Get (WYSIWYG)

42. Language versus Action
 actions do not always speak louder than words!
 Image projected as DM – interface replaces
underlying system
 language paradigm
 interface as mediator
 interface acts as intelligent agent
 programming by example is both action and
language

43. Hypertext
 1945 – Vannevar Bush and the
memex
 key to success in managing
explosion of information
 mid 1960s – Nelson describes
hypertext as non-linear browsing
structure
 hypermedia and multimedia
 Nelson's Xanadu the first hypertext
project still a dream today
The memex (a portmanteau of "memory"
and "index" or "memory" and "extender")
is the name of the hypothetical proto-
hypertext system that Vannevar Bush
described in his 1945 The Atlantic
Monthly article "As We May Think".

44. Hypertext and Hypermedia
 Ted Nelson coined the term hypertext in
1963.
 Also credited for being first to use words
like hypermedia.
 Hypertext spawned from the concept of
Memex (Vannevar Bush):a mechanical
desk linked to an extensive archive of
microfilms, able to display books, writings,
or any document from a library.
 Earlier hypertext: footnotes

45. Example of hypertext
 <html>
<body>
<h1>My First Heading</h1>
<p>My first paragraph.</p>
</body>
</html>

46. Multimodality
 a mode is a human
communication channel
 emphasis on simultaneous use
of multiple channels for input
and output

47. Computer Supported Cooperative
Work (CSCW)
 CSCW removes bias of single user / single
computer system
 Can no longer neglect the social aspects
 Electronic mail is most prominent success

48. The World Wide Web
 Hypertext, as originally realized, was a closed
system
 Simple, universal protocols (e.g. HTTP) and
mark-up languages (e.g. HTML) made publishing
and accessing easy
 Critical mass of users lead to a complete
transformation of our information economy.

49. World wide web

50. Agent-based Interfaces
 Original interfaces
 Commands given to computer
 Language-based
 Direct Manipulation/WIMP
 Commands performed on “world” representation
 Action based
 Agents - return to language by instilling proactivity
and “intelligence” in command processor
 Avatars, natural language processing

51. Ubiquitous Computing
“The most profound technologies are
those that disappear.”
Mark Weiser, 1991
Late 1980’s: computer was very
apparent
How to make it disappear?
 Shrink and embed/distribute it in the
physical world
 Design interactions that don’t demand our
intention
computing is made to
appear everywhere
and anywhere

52. Sensor-based and Context-aware
Interaction
 Humans are good at recognizing the “context” of
a situation and reacting appropriately
 Automatically sensing physical phenomena (e.g.,
light, temp, location, identity) becoming easier
 How can we go from sensed physical measures
to interactions that behave as if made “aware” of
the surroundings?

53. Summary
 Today we have covered
 Examples of effective strategies for building interactive
systems provide paradigms for designing usable interactive
systems.
 The evolution of computing usability paradigms also provides
a good perspective on the history of interactive computing.
 Paradigms range from the introduction of time-sharing
computers, through the WIMP and web, to ubiquitous and
context-aware computing