1. Operating Systems Advanced OS - C

2. OS Advanced The User Interface

3. OS Advanced The OS provides a user interface or shell for the user to interact with the OS

4. OS Advanced Types of User Interfaces Command Interface Menu Interface Graphical User Interface Expert User Interface Web-Form Interface

5. OS Advanced Command Interface Requires the user to type brief, cryptic commands Example: MS-DOS Requires considerable user training

6. OS Advanced Command Interface

7. OS Advanced Menu Interface Presents a list of available options Example: Norton Commander Easier to use, but can be time consuming

8. OS Advanced Menu Interface

9. OS Advanced Graphical User Interface Presents a selection of windows, icons, menus and pointers Example: Windows XP Easier to use, but consume more computer resources to function

10. OS Advanced Graphical User Interface

11. OS Advanced Expert System Interface Uses natural-language processing Example: Voice Recognition Requires a powerful computer and lots of memory

12. OS Advanced Web-Form Interface Like the Internet Example: WWW Easier to train users used to the Internet & WWW

13. OS Advanced Human – Computer Interface A key to understanding the evolution of user interfaces is a sense of what a computer can accomplish in an “instant”

14. OS Advanced An “Instant” A very short, almost imperceptible space of time. It happens so fast we are unaware that time has passed. Few people are capable of sensing anything that happens in less then 0.001 seconds.

15. OS Advanced An “Instant” We define and “instant” as 0.001 seconds

16. OS Advanced A computer must be capable of accepting, processing and outputting the results in an “instant”

17. OS Advanced In the 1970s computers could process one line of data in 0.001 seconds, thus the Command Interface

18. OS Advanced In the early 1980s computers could process 25 lines of data in 0.001 seconds, thus the Menu Interface

19. OS Advanced In the late 1980s computers could process EGA, VGA, then SVGA graphics in 0.001 seconds, thus the GUI emerged

20. OS Advanced Eventually computer will be fast enough for Expert System Interfaces or natural-language voice recognition interfaces

21. OS Advanced The de facto standard interface is defined by the amount of processing a computer can do within a human “instant”

22. OS Advanced The best way to learn a computer interface is to use it…..Duh!... The best way to learn a computer interface is to use it…..Duh!...

23. OS Advanced Questions?