1. Software: Systems and Application Software
C H A P T E R 4
Software:
Systems and Application Software

2. Software Computer programs Documentation
Sequences of instructions for the computer
Documentation
Describes the program functions
Helps users operate the computer system
continued...

3. Software System software Computer system platform Application software
The set of programs designed to coordinate the activities and functions of the hardware and various programs throughout the computer system
Computer system platform
The combination of a particular hardware configuration and systems software
Application software
Programs that help users solve particular computing problems

4. Classifying Software by Type and Sphere of Influence
[Table 4.1]

5. Utility Programs Merge and sort sets of data
Keep track of computer jobs being run
Compress files of data before they are stored or transmitted over a network
Perform other important repetitive tasks

6. Examples of Utility Programs
[Table 4.2]

7. Operating Systems
Operating System: A set of computer programs that control the computer hardware to support users’ computing needs.
Operating System Tasks:
Common hardware functions
User interfaces
Hardware independence
Networking capability
Memory management
Processing tasks
Access to system resources
File management

8. Role of the Operating System
The operating system, as well as other systems software, functions as a buffer between application software and hardware.
[Figure 4.2]

9. User Interface Allows users to access and command the computer system
Command-based user interface
Requires that text commands be given to the computer to perform basic activities

10. User Interface Graphic user interface (GUI)
Uses pictures (icons) and menus displayed on screen to send commands to the computer system

11. Advantages of Using a GUI
Intuitive environment
Consistent applications
Flexible applications
Cut and paste between applications
Easy to use applications
Undo capability
Confirmation of important operations

12. Memory Management Virtual memory Paging
Allocates space on disk to supplement the immediate, functional memory capacity of RAM
Paging
Stores currently needed pages of a number of programs in RAM while the rest of these programs wait on the disk

13. How the Operating System Controls Physical Access

14. Virtual Memory
[Figure 4.5]

15. Processing Tasks Multitasking Multithreading Time-sharing
Allows a user to run more than one application at a time
Multithreading
Multitasking within a single application
Time-sharing
Allows more than one person to use a computer system at the same time

16. Popular Operating Systems
PC-DOS and MS-DOS
DOS with Windows
OS/2
Windows 95
Microsoft Windows CE
Apple computer OS
System 7.6
Future Mac OS developments
Widows NT and NT Workstation
Unix
Multiple Virtual Storage/Enterprise Systems Architecture

17. How Application Software Supports Business Objectives
Applies to specific organizational activities and functions
Provides significant internal efficiencies and supports corporate goals

18. Types of Application Software
Proprietary software
One-of-a-kind program for a specific application
Off-the-shelf software
Existing software program
Customized
Off-the-shelf program modified or customized (in-house or externally)

19. Proprietary Application Software
In-house development
Software developed by an enterprise for its own use
Contract software
Proprietary software developed for a particular company

20. Sources of Software: Proprietary and Off-the-Shelf
[Figure 4.6]

21. Personal Application Software
Personal productivity tool
PC software for specialized tasks
Word processing
Spreadsheet analysis
Database applications
Graphic programs
On-line information services
Software suites

22. Object Linking and Embedding (OLE)
Process where text can be copied or graphics can be embedded from one document or program into another
Server application
Supplies objects that can be placed into other applications
Client application
Accepts objects from other applications

23. Object Linking and Embedding (OLE)
Copying
Does not change data between applications
Linking
A relational database process
Can occur when two tables share at least one common element
Embedding
A process of putting one object into another document

24. Workgroup Software
Allows two or more people in a group to work effectively together to use word processing, databases, spreadsheets, and related software packages
Also called groupware

25. Enterprise Software Software that benefits the entire organization
[Figure 4.16]

26. Software Issues and Trends
Software licensing
Software upgrades
Shareware
Author expects a modest payment for the privilege of using the software
Freeware
Software that is free
Open systems
A vision of computing products that work together

27. Protection of Software Copyrights
Poster p171

28. Programming Languages
Coding schemes that provide instruction to the computer system so that it can perform a processing activity
Syntax
The set of rules that a language has
Program Language Standards
A set of rules that describe how programming statements should be written
Developed by the American National Standards Institute (ANSI)

29. Characteristics of Programming Languages
[Figure 4.17]

30. Evolution of Programming Languages
[Table 4.11]

31. Machine Language (1GLs)
First generation programming language
Instructions written in binary code (using only 0s and 1s)
Considered a low-level language
[Figure 4.18]

32. Assembly Language (2GLs)
Second generation programming language
Replaces binary digits with symbols that can be more easily understood
All languages beyond first generation are called symbolic languages.

33. High-Level Languages (3GLs)
Third-generation languages
Use English-like statements and commands

34. Query and Database Languages (4GLs)
Fourth-generation languages
Less procedural and more English-like than high-level languages
Features
Query and database abilities
Code-generation abilities
Graphics abilities

35. Natural and Intelligent Languages (5GLs)
Fifth generation programming languages
Used to create programs employing artificial intelligence and expert system technology
Natural languages
Allow end users to access stored data and interact with the computer using ordinary words

36. Object-Oriented Programming Languages
Allow interaction of programming objects
Encapsulation
Process of grouping items into an object
Polymorphism
Allows development of one routine that will work with multiple objects
Inheritance
Allows objects in a group of objects to take on characteristics of other objects in the same group or class of objects
Reusable code
Instruction code that can be reused in different programs for a variety of applications

37. Object-Oriented Programming Languages
Smalltalk
C++
Java

38. Language Translators
Systems software that converts source code into its equivalent in machine language
Source code
High-level program code that is converted by the language translator
Object code
Machine language code that is converted from the source code

39. Interpreter
A language translator that translates one program statement at a time as the program is running
[Figure 4.20]

40. How a Compiler Works
A compiler is a language translator that converts a complete program into machine language to produce a program that the computer can process in its entirety.
[Figure 4.21]

41. Information Systems Principles
In choosing an organization's operating system, make a selection based on the needs and cost constraints of the organization.

42. Information Systems Principles
Effective implementation of application software can improve efficiency and support corporate goals. Careful analysis of goals and needs should precede any decision as to the best approach for acquiring application software.

43. Information Systems Principles
Choose the programming language appropriate to the task at hand and one that is consistent with the organization’s strategic technical direction.