1
• Human
– the end-user of a program
– the others in the organization
• Computer
– the machine the program runs on
– often split between clients & servers
• Interaction
– the user tells the computer what they want
– the computer communicates results
Human-Computer
Interaction
(HCI) is a term refer to the
understanding and designing of
different
relationships
people and computers
between

system concerned to study,
design, construction and
implementation of human-
centric interactive computer
systems

basic goal :improve the interactions between
users and computers by making computers
more usable and receptive to the user's needs.

A long term goal :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.
Use and Context
Social Organization and Work
Human-Machine Fit and Adaptation
Application Areas
Human
Computer
Dialogue
Techniques
Human
Information
Processing
Language,
Communication
and Interaction
Evaluation
Techniques
Computer
Graphics
Aa
Ergonomics
Dialogue
Genre
Input and
Output Devices
Example Systems
and Case Studies
Design
Approaches
Development Process
Dialogue
Architecture
Implementation
Techniques and Tools
1- Human information
processing, memory,
perception, motor
skills, attention,
problem-solving ,
learning and
skill
acquisition, motivation
, conceptual models.
,2-Language, communication and interaction
• aspects of language
- syntax, semantics, pragmatics; conversational
interaction, specialized languages
3- Ergonomics
•
anthropometric and
physiological
characteristics of
people and their
relationship to
workspace and the
environment.
• Business view:
– to use humans more productively/effectively
– the human costs now far outweigh hardware and
software costs
• Personal view:
– people view computers as appliances, and want
it to perform as one
• Marketplace view:
– everyday people using computers
• now expect “easy to use system”
• not tolerant of poorly designed systems
– if product is hard to use, people will seek
other products
• The system view:
– complex human
– complex computer
– complex interface between the two
• The human factors view:
– humans have limitations
– errors are costly in terms of
• loss of time
• loss of money
• loss of morale
– design can cope with such limitations!
• The social view:
• Computers contribute to critical parts of our
society, and cannot be ignored
– educate our children
– take medical histories and provide expert
advice
– keep track of our credit worthiness
 The
1st is concerned with technological
innovation to meet the user's particular needs
 Better output devices, like display monitors
 Improved input devices, like electronic pen
 The 2nd is concerned with the cognitive characteristics
(background and knowledge of the users) including:
• Their knowledge representation, reasoning strategies,
and the types of decisions they prefer in solving
problems.
The 3rd is concerned with the tasks which
the users wish to carry out.
 Is it complex tasks (e.g. controlling a nuclear
power station) or simple tasks (e.g. writing
letters).
The 4th is concerned with the types of
interfaces available.

HCI is undoubtedly a multi-disciplinary subject. The
ideal designer of an interactive system would have
expertise in a range of topics:

psychology and cognitive science
to give his knowledge of the users perceptual
Cognitive and Problem- solving skills.
 ergonomics
for the user’s physical capabilities
 sociology
to help her understand the wider
context of the interaction.
 computer
science and engineering to be able
to build the necessary technology.
 business
 Graphic
to be able to market it
design to produce an effective
interface presentation.
 technical
writing to produce the manuals,
• Interaction designers
– involved in the design of all the interactive aspects of
a product
• User interface architect
– Term often used for member of software team for
interface issues
• Usability engineers
– focus on evaluating products, using usability methods
and principles
• Web designers
– develop and create the visual design of websites, such as
layouts
• Information architects
– how to plan and structure knowledge rich interactive products
Unfortunately
for us, there is no general
and unified theory of HCI that we can
present. there is an underlying principle
that forms the basis of our own views on
HCI ,and it is captured in our claim that
people use computers to accomplish
work.

This outlines the three major issues of concern:

the people

the computers
 the

tasks that are performed.
The system must support the user’s task, which
gives us a fourth focus, usability…..
HCI depends on computer operating as
an intermediary, achieving appropriate
interaction through a variety of I/O
devices