6. Interface Metaphors

1. 6. Interface Metaphors 6. Interface Metaphors

2. Metaphors • Metaphors convey an abstract concept in a more familiar and accessible form. • A widely quoted example can be found in Shakespeare's As You Like It: • "All the world's a stage...“ • Metaphors are widely used to make use of users’ existing knowledge when learning new computer systems. 6. Interface Metaphors

3. Computer has a QWERTY keyboard Typewriter has a QWERTY keyboard AND Keys should have same effect as they do on a typewriter Verbal Metaphors • Verbal metaphors are useful tools to help users to understand a new system. • This perceived similarity activates the user’s ‘typewriter’ schema 6. Interface Metaphors

4. Verbal Metaphors • These links provide basic foundation from which users develop their mental models. • Knowledge about a familiar domain (typewriter) in terms of elements and their relation to each other is mapped onto the unfamiliar domain (computer). • Elements: keyboard, spacebar, return key • Relations: hit only one character key at a time, hitting a character key will result in a letter being displayed on a visible medium 6. Interface Metaphors

5. Verbal Metaphors • Dissimilarities can cause problems for learners. • For example, the backspace key on a typewriter moves the carriage back, while on a word processor it usually deletes a character. • However, as they become aware of the discrepancies, they can develop a new mental model 6. Interface Metaphors

6. Advance Organisers • Verbal metaphors provided in advance can aid learning. • For example, Foss (1982) studied the effect of describing a metaphor for a system to new users before they start learning. • This is called an advance organiser. • In this case file creation and storage were explained in terms of a filing cabinet metaphor 6. Interface Metaphors

7. Virtual Interface Metaphors • Verbal metaphors try to explain the use of a computer system in terms of something that it resembles. • Xerox in the late 1970’s realised the potential of deliberately designing interfaces to be more like the real world. • Instead of using verbal metaphors they went further and designed an interface metaphor for the Star system. • The overall organising metaphor on the screen was the desktop, resembling the top of a real office desk. 6. Interface Metaphors

8. Xerox Star (1980) 6. Interface Metaphors

9. Apple Macintosh (1984) 6. Interface Metaphors

10. Windows 1.0 (1985) 6. Interface Metaphors

11. Windows 2.0 (1987) 6. Interface Metaphors

12. DR GEM (1988) 6. Interface Metaphors

13. NextStep (1988) 6. Interface Metaphors

14. Windows 3.1 (1993) 6. Interface Metaphors

15. Macintosh System 7 (1993) 6. Interface Metaphors

16. Windows 95 (1995) 6. Interface Metaphors

17. Windows XP (2001) 6. Interface Metaphors

18. MacOS X (2001) 6. Interface Metaphors

19. Longhorn (2006?) 6. Interface Metaphors

20. Composite Metaphors • A problem with the ‘metaphor as model’ approach is the difficulty of introducing new functionality which does not fit into the interface metaphor. • Designers have got round this by introducing composite metaphors. These allow the desktop metaphor to include objects which do not exist in the physical office, for example: • menus • windows • scroll bars (these make use of the concept of unrolling a scroll, or rolled-up document) 6. Interface Metaphors

21. Composite Metaphors • It might be assumed that users may have difficulty with composite metaphors. • In general it has been found that people can deal with them rather well and can develop multiple mental models. • Some composite mental models can cause confusion. For example, on a Macintosh, you can eject a disk by dragging it to the trash – you retrieve it by throwing it away. 6. Interface Metaphors

22. Metaphors - Applications • The desktop metaphor has been used successfully for operating systems. • However, other metaphors have been developed for specific types of applications 6. Interface Metaphors

23. Data Storage • Metaphor: Filing system • Familiar knowledge: files, folders, storing files, retrieving files 6. Interface Metaphors

24. Spreadsheets • Metaphor: ledger sheet • Familiarknowledge: columnar tables, calculations 6. Interface Metaphors

25. The Web • Metaphor: Travel • Familiarknowledge: going from place to place 6. Interface Metaphors

26. Online Shopping • Metaphor: Shopping cart • Familiarknowledge: adding items, checking out 6. Interface Metaphors

27. Graphics Applications • Metaphor: Toolbox 6. Interface Metaphors

28. Virtual Reality 6. Interface Metaphors

29. Web Sites 6. Interface Metaphors

30. Web Sites 6. Interface Metaphors

31. Interface Elements • Tabs 6. Interface Metaphors

32. Interface Elements • Progress Bars • Metaphor: progress is to the right (orientational metaphor) • Based on direction of reading – highly cultural, as some cultures read from right to left. • Icons • Symbolic icons use metaphors to convey their meaning – e.g. a globe to represent the World Wide Web or the magnifying glass icon in a photo manipulation program to represent zooming in on an image. 6. Interface Metaphors

33. Pervasive Computing • Pervasive computing is the trend towards increasingly ubiquitous connected computing devices in the environment • also known as ubiquitous computing • In these devices, the computer interface moves away from the desktop and the interface metaphor is invisible to the user • One user, many computers 6. Interface Metaphors

34. Pervasive Computing • Xerox's Palo Alto Research Center (PARC), for example, has been working on pervasive computing applications since the 1980s • IBM's project Planet Blue, for example, is largely focused on finding ways to integrate existing technologies with a wireless infrastructure • Carnegie Mellon University's Human Computer Interaction Institute (HCII) is working on similar research in their Project Aura • Massachusetts Institute of Technology (MIT) has a project called Oxygen. 6. Interface Metaphors

35. Pervasive Computing 6. Interface Metaphors