Transcript Software

Information Systems Software
MIS 320
Kraig Pencil
Summer 2014
PPT Slides by Dr. Craig Tyran & Kraig Pencil
A. Game Plan
• Application
Software
• Systems Software
– Operating System
– Support Programs
• Compatibility
issues
• Role of Microsoft
B. Application Software
1.
2.
What is it?
–
SW that performs a specific task for
user
–
Examples?
Categories
–
Personal application software
(a.k.a. personal productivity software)
• e.g., MS Office
–
Entertainment
• e.g., games, music, etc.
–
Business application software
• e.g., payroll, inventory, DSS
C. Systems Software
1. Definition
–
Software that manages and
supports the computer system
2. Categories
–
–
Operating system
Support programs
C. Systems Software
3. Operating system (OS)
– Supervises the overall operation of computer
– Serves as a critical link in computer operations
 … a bridge/interpreter
–
–
Operating
System
DRIVERS
Application
Software
hardware
(and the user*)
application software
other computers
API
–
* Of course, the user interacts with the operating system
through the hardware: mouse, keyboard, screen, etc.
Network
5
D. Operating System: Functions
1.
Processor Management
–
A computer often needs to juggle several processes at
one time (i.e., multitasking)
•
Examples???
–
A good OS handles multitasking without user even knowing
about the “juggling”
–
If too many processes at once …
 “Thrashing” occurs as CPU swaps back and forth among
processes
–
Some CPU’s contain 2 two or more processors that run
simultaneously.
D. Operating System: Functions
2. Memory
management
–
–
Processes
require
“memory
space” (i.e.,
“primary
storage”)
OS 
Allocates
memory
across
processes
D. OS: Functions (cont.)
3. Storage management
–
–
Allows users to save, delete, access, & organize files stored
in long-term “secondary storage”
OS  Keeps track of physical location and characteristics of
files
4. Device management
–
“Devices” include
• Keyboard, mouse, printer,
DVD player, etc.
D. OS: Functions (cont.)
4. Device management (cont.)
–
OS needs to interact with the devices (e.g. printers) of many makes and
models … each with their own design, abilities and “languages”
• How to translate signals between OS and devices?
OS
–
Devices
Software “drivers” are used to translate the interactions
• This is why you often need to load the “driver” SW when you add a
new device (mouse, printer, etc.) to your PC system
D. OS: Functions (cont.)
5. User interface
–
–
This is what the
user sees
Recall earlier figure
of OS linkages
How easy is it to … ?
– Create, store, and manage files?
– Start software applications?
– Manage input or output devices?
•
Old “command-line” systems
used keyboards only – and only
letters and numbers on screen.
•
Today we prefer a Graphical
User interface, a GUI, with a
mouse and point and click.
•
And in the future? …
http://www.youtube.com/watch?v=oO0yzTW62xQ
D. OS: Functions (cont.)
6. Application Program Interface (API)
–
–
–
–
This is what the application software sees
Recall earlier figure of OS linkages
The API is a set of rules and specifications that allows application
software to easily interact with various CPU and hardware designs
Application developers use the API rules when they write their
applications
Operating
System
A
P
I
Application
Software
E. Support Programs
1. Examples include
–
Anti-virus software
•
–
Connectivity software
•
–
Scan/eliminate viruses!!!
e.g., Use to connect to the Internet
Housekeeping software
•
•
•
•
Monitor and optimize performance
Backup and recover data
Defragment files
… and so on.
F. Popular OS
1. OS for microcomputers
–
Examples?
2. OS and other hardware platforms
–
–
Unix: Micros, workstations, mainframes
Linux: Micros (see above), workstations, mainframes,
supercomputers
•
•
•
–
“Open source” software
Can offer lower-cost, solid performance
Businesses have shown interest (e.g., servers, transaction
systems)
MVS (Multiple Virtual Storage): Mainframe
computers made by IBM
G. OS and Compatibility Issues
OS is typically designed for a specific HW “platform”
(i.e. “CPU” model)
1.
–
Examples of HW “platforms”
•
•
•
2.
Intel-based PC
Apple (PowerPC and Intel)
IBM mainframe
Many organizations have multiple types of HW
–
3.
OS are designed to work with a given HW (or vice versa)
 Multiple types of OS may exist within an organization
Application SW is typically designed for
a specific OS
–
Example (see following slide)
Operating
System
A
P
I
Application
Software
Software Downloads and OS Options
Different
software
for
different
OS
G. OS and Compatibility Issues (cont.)
4. If an organization has mulitple computer
HW platforms and/or multiple OSs ….
 Potential compatibility problems
5. Examples of potential problems
– Application SW that works on one
computer may not work on another
computer
 Can be difficult to standardize
SW applications
G. OS and Compatibility Issues (cont.)
5. Examples of potential problems (cont.)
–
Different types of computer systems may not be
compatible
e.g., IS For Finance Dept vs. Marketing Dept
 Need to “patch together”
different HW and SW
for communication
–
IS support staff needs to learn different “languages”
–
Lots of headaches for all ….
H. Role of Microsoft
1. In past years, Microsoft (MS) has had a solid
position with regard to PC operating systems
2. Based on what we have discussed regarding the
general role of OS software, how has MS’s
position regarding OS provided MS with a source
of power in the field of PC computing?
–
–
With regard to application software market?
With regard to hardware market?