1. Human Computer Interaction
Definition, Importance and Scope

2. Definition, Importance and Scope
The field of Human-Computer Interaction ( HCI ) attempts to understand and shape the way people interact with computers: The processes they engage in, the resources they use and the impact they accomplish.
HCI is the study of how people interact with computers , the HCI is about how to allow humans and computers to interact toward some common goal.
The term human-computer interaction (HCI) was adopted in the mid-1980s as a means of describing the user interface system.

3. Human Computer Interface (HCI)
A discipline for the
Design,
Implementation,
and Evaluation
of interactive systems for human use.
Or …
User-centered software engineering

4. Definition, Importance and Scope
The importance of HCI is to develop or improve the safety, utility خدمة, effectiveness فعالية, efficiency نجاعة, and usability of systems.
Efficiency refers to the ability to produce maximum output from the given input with the least waste of time, effort, money, energy and raw materials. 
Effectiveness refers to the degree of closeness of the achieved objective with the predetermined goal.

5. Definition, Importance and Scope
HCI consists of three parts:
The user: it means an individual user, a group of users working together, or a sequence of users in an organization, each dealing with some part of the task or process.
The computer: It means any technology ranging from the general desktop computer to a large scale computer system, a process control system or an embedded system.
The interaction: It means any communication between a user and computer, be it direct or indirect.

6. Definition, Importance and Scope
This may seem a very limiting approach to HCI, but it covers the bulk of the field today.
Some examples of HCI scope:-
Clerical work supported by Office systems.
Managerial work supported Enterprise Resource Planning.
Project Management Software, group and individual Decision Support Systems and Professional work supported by an Online library.

7. Who is involved in HCI?
HCI is undoubtedly a multi-disciplinary subject. The ideal designer of an interactive system would have expertise in a range topics:
Psychology and cognitive science: to give him knowledge of the user’s perceptual.
Cognitive and problem-solving skills.
Ergonomics ( or Human Factors ): for the user’s physical capabilities.
Sociology: to help him understand the wider context of the interaction.

8. Who is involved in HCI? Cont.
Computer science and engineering: to be able to build the necessary technology.
Business: to be able to market it.
Graphic design: to produce an effective interface presentation.
Technical writing: to produce the manuals.

9. Who is involved in HCI? Cont.
It is not possible to design effective interactive systems from one discipline in isolation.
HCI draws in many disciplines, but it is in computer science and systems design that it must be accepted as a central concern, for system design it is an essential part of the design process.
HCI involves the design, implementation and evaluation of interactive systems in the context of the user’s task and work.

10. Factors in HCI Organizational: job design, roles, policies,..
There are a large number of factors which should be considered in the analysis and design of a system using HCI principles.
Organizational: job design, roles, policies,..
Environmental: noise, heating, lighting,..
Health: stress, headaches ,..
The user : motivation, satisfaction, experience,..
Comfort : equipment, layout,..
User interface : I/O devices, color scheme, icons, help,..
Task : complexity, novelty, allocation, monitoring,..
Constraints : costs, timescales, staff, equipment, building,..
System functionality : hardware, software, network,..
Productivity : output, quality, costs, errors, production time,..

11. The User Interface
The user interface is the system which helps users communicate with the computer system and/or the application system

12. UI Components Most common GUI configuration
WIMP – window, icon, mouse, pointer
Command Line (CLI) configurations can vary
Scripts
TUI – looks like graphic, but comprised of text characters
Do we need to show and define other related acronyms such as PUI, Bob, 3dwm, FSV, ZUI, TUI?
Give examples of each. GUI: MS Windows, CLI: DOS, TUI: Cpower
Good and bad points of each!
GUI: looks nice, familiar, easier to use for beginners
BUT! Can be too simple for experienced users, requires a lot more processing power and memory
CLI: Requires less computing power, runs faster on less processing power
BUT! too difficult for less computer literate users! Also not as pretty.
Text User Interface (TUI)

13. Types of User Interfaces
There are several types of user interfaces:
Natural-language interfaces
Question-and-answer interfaces
A menu interface
Form-fill interfaces
Command-language interfaces
Graphical User Interfaces (GUIs)

14. What is a Graphical User Interface ?
A graphical user interface (GUI) is a human-computer interface (i.e., a way for humans to interact with computers) that uses windows, icons and menus and which can be manipulated by a mouse (and often to a limited extent by a keyboard as well).
Explanation: this mixed type of interface may be the most practical one in medical fields. Think about the medical order with prescriptions, GUI is really hard to display all medicines and related orders in a simple way. If nesting CLUE into GUI, the situation will be much easier for clinical personnel. Also, an individualized recipe or therapy combo can be easily input or modified in batch processing mode in CLUE, but not in GUI.
However, be careful of CLI! If doctors get too accustomed to hot key commands, they may make serious and negligent errors if they make mistakes while typing. Results could be deadly!
Most likely to deal with a GUI in a clinical setting, maybe with some CLI elements (as mentioned above).

15. Graphical UIs (GUIs)
Some old systems still use command-line or text-based UIs
Most systems today use GUIs
Windows: simultaneous views
Icons: data, functions
Menus: choice of options, memory aids
Pointing: trackball, touchpad, mouse, eye
Graphics: charts, tables, diagrams
Static or dynamic
Copyright © 2003 M. E. Kabay. All rights reserved.

16. Human factors in interface design
Limited short-term memory
People can instantaneously remember about 7 items of information. If you present more than this, they are more liable to make mistakes.
People make mistakes
When people make mistakes and systems go wrong, inappropriate alarms and messages can increase stress and hence the likelihood of more mistakes.
People are different
People have a wide range of physical capabilities. Designers should not just design for their own capabilities.
People have different interaction preferences
Some like pictures, some like text.

17. Design principles User familiarity Consistency Minimal surprise
The interface should be based on user-oriented terms and concepts rather than computer concepts. For example, an office system should use concepts such as letters, documents, folders etc. rather than directories, file identifiers, etc.
Consistency
The system should display an appropriate level of consistency. Commands and menus should have the same format, command punctuation should be similar, etc.
Minimal surprise
If a command operates in a known way, the user should be able to predict the operation of comparable commands

18. Design principles Recoverability User guidance User diversity
The system should provide some resilience to user errors and allow the user to recover from errors. This might include an undo facility, confirmation of destructive actions, 'soft' deletes, etc.
User guidance
Some user guidance such as help systems, on-line manuals, etc. should be supplied
User diversity
Interaction facilities for different types of user should be supported. For example, some users have seeing difficulties and so larger text should be available