1. 1 THE USER INTERFACE Basic Principles

2. 2 Requirements System Design Detailed Design Implementation Installation & Testing Maintenance User Interface Model

3. 3 processing - transformation inputoutput data USER INTERFACE

4. 4 Complete System Design Major categories: –functional element –information / data element –user interface –quality

5. 5 User Interface Design separate set of design concerns –end-user driven –representation mechanisms separate design and implementation language less formalised than other design issues – rules and principles –(horizontal) prototyping

6. 6 Functions of the User Interface (re-)presents –system behaviour –information / data interacts with –the end-user –the system

7. 7 H C I HCI - Human Computer Interface the end-user oriented side of the user-interface computer science overlaps with cognitive science

8. 8 Issues in HCI Design study of people –human perception –user-profile technology issues –styles of interaction –consistency –user-friendliness

9. 9 Customer and End-User customer –the one who pays end-user –the one who has to live with the system –applies functionality and information –gets frustrated with the user-interface

10. 10 Human Perception dominating senses in human-computer interaction: –visual –auditory ===> graphical communication ===> text ===> with multi-media bonus

11. 11 Human Perception short term memory –immediate access, “buffer” long term memory –knowledge ===> use appropriately ===> do not “overload” ===> the magical number 7

12. 12 User Skills - Interface Handling depends on frequency of use of the system different needs for syntax support, navigation, interaction style... ===> “power” user ===> occasional user ===> provide for both types (adaptability)

13. 13 User Skills - Level of Expertise depends on domain specific knowledge capacity to understand / provide information determines style of information representation ===> expert user ===> “layman” ===> different systems?

14. 14 User Profile - Beginner / Novice Frequency of use: –new to the system Expertise: –appropriate (expert or layman), but must be mapped to the given representation, structure, etc. ===> provide guidance for the use of the HCI ===> help with system contents

15. 15 User Profile - Advanced User Frequency of use: –part of daily routine –part of the job profile Expertise: –high ===> provide shortcuts, special functions ===> allow for parameterization of the HCI ===> allow for extension of the HCI

16. 16 User Profile - Occasional User Frequency of use: –on occasion (with varying intensity) –has past experience with the system Expertise: –good and stable ===> wide variety of possible profiles ===> find the deficiency (syntactic / semantic) ===> provide variable support

17. 17 End of Section 5a coming up: styles of interaction