Operating Systems Operating Systems Advanced OS - C Advanced OS - C
Dec 13, 2015
Operating SystemsOperating Systems
Advanced OS - CAdvanced OS - C
OS AdvancedOS Advanced
The User InterfaceThe User Interface
OS AdvancedOS Advanced
The OS provides a user interface or The OS provides a user interface or shell for the user to interact with the shell for the user to interact with the
OSOS
OS AdvancedOS Advanced
Types of User InterfacesTypes of User Interfaces
Command InterfaceCommand Interface
Menu InterfaceMenu Interface
Graphical User InterfaceGraphical User Interface
Expert User InterfaceExpert User Interface
Web-Form InterfaceWeb-Form Interface
OS AdvancedOS Advanced
Command InterfaceCommand Interface
Requires the user to type brief, Requires the user to type brief, cryptic commandscryptic commands
Example: MS-DOSExample: MS-DOS
Requires considerable user trainingRequires considerable user training
OS AdvancedOS AdvancedCommand InterfaceCommand Interface
OS AdvancedOS Advanced
Menu InterfaceMenu Interface
Presents a list of available optionsPresents a list of available options
Example: Norton CommanderExample: Norton Commander
Easier to use, but can be time Easier to use, but can be time consumingconsuming
OS AdvancedOS AdvancedMenu InterfaceMenu Interface
OS AdvancedOS Advanced
Graphical User InterfaceGraphical User Interface
Presents a selection of windows, Presents a selection of windows, icons, menus and pointersicons, menus and pointers
Example: Windows XPExample: Windows XP
Easier to use, but consume more Easier to use, but consume more computer resources to functioncomputer resources to function
OS AdvancedOS AdvancedGraphical User InterfaceGraphical User Interface
OS AdvancedOS Advanced
Expert System InterfaceExpert System Interface
Uses natural-language processingUses natural-language processing
Example: Voice RecognitionExample: Voice Recognition
Requires a powerful computer and Requires a powerful computer and lots of memorylots of memory
OS AdvancedOS Advanced
Web-Form InterfaceWeb-Form Interface
Like the InternetLike the Internet
Example: WWWExample: WWW
Easier to train users used to the Easier to train users used to the Internet & WWWInternet & WWW
OS AdvancedOS Advanced
Human – Computer InterfaceHuman – Computer Interface
A key to understanding the A key to understanding the evolution of user interfaces is a evolution of user interfaces is a sense of what a computer can sense of what a computer can
accomplish in an “instant”accomplish in an “instant”
OS AdvancedOS Advanced
An “Instant”An “Instant”
A very short, almost imperceptible A very short, almost imperceptible space of time. It happens so fast space of time. It happens so fast
we are unaware that time has we are unaware that time has passed. Few people are capable of passed. Few people are capable of
sensing anything that happens in sensing anything that happens in less then 0.001 seconds.less then 0.001 seconds.
OS AdvancedOS Advanced
An “Instant”An “Instant”
We define and “instant” as We define and “instant” as
0.001 seconds0.001 seconds
OS AdvancedOS Advanced
A computer must be capable of A computer must be capable of accepting, processing and accepting, processing and
outputting the results in an “instant”outputting the results in an “instant”
OS AdvancedOS Advanced
In the 1970s computers could In the 1970s computers could process one line of data in 0.001 process one line of data in 0.001
seconds, thus the Command seconds, thus the Command InterfaceInterface
OS AdvancedOS Advanced
In the early 1980s computers could In the early 1980s computers could process 25 lines of data in 0.001 process 25 lines of data in 0.001 seconds, thus the Menu Interfaceseconds, thus the Menu Interface
OS AdvancedOS Advanced
In the late 1980s computers could In the late 1980s computers could process EGA, VGA, then SVGA process EGA, VGA, then SVGA
graphics in 0.001 seconds, thus the graphics in 0.001 seconds, thus the GUI emergedGUI emerged
OS AdvancedOS Advanced
Eventually computer will be fast Eventually computer will be fast enough for Expert System enough for Expert System
Interfaces or natural-language voice Interfaces or natural-language voice recognition interfacesrecognition interfaces
OS AdvancedOS Advanced
The de facto standard interface is The de facto standard interface is defined by the amount of defined by the amount of
processing a computer can do processing a computer can do within a human “instant”within a human “instant”
OS AdvancedOS Advanced
The best way to learn a computer The best way to learn a computer interface is to use it…..Duh!...interface is to use it…..Duh!...
OS AdvancedOS Advanced
Questions?Questions?