Management Information Systems, 4th Edition 1

Chapter 5

Information Systems

in Business: Software

Management Information Systems, 4th Edition 2

Learning Objectives

• Explain why professionals must keep abreast of

software developments

• Enumerate the different generations of

programming languages and explain how they

differ

• Explain the difference between application

software and system software

Management Information Systems, 4th Edition 3

Learning Objectives (Cont.)

• Compare the strengths and weaknesses of

tailored software versus off-the shelf software

• Cite the latest major developments in

application and system software

• List characteristics that are important in

evaluating packaged software applications for

business use

Management Information Systems, 4th Edition 4

Software: “Instructions

to the Computer”

• A computer program is a series of instructions to a

computer to execute any and all processes

• Computers only “understand” instructions consisting

of electrical signals alternating between two states

Management Information Systems, 4th Edition 5

Software: Instructions

to the Computer (Cont.)

• Application software enables users to complete a

particular task, such as word processing

• System software enables application software to run

on a computer and manages the interaction between

hardware devices

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Programming Languages

• Abbreviated forms of instructions that translate

into machine language

• New programming languages make programming

easier for people who are not necessarily hardware

experts

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Programming Languages (Cont.)

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First Generation: Machine

Languages (ML)

• Only languages computers can directly interpret

to carry out instructions

• ML coding: time-consuming and error-prone

• ML programmers: concerned with hardware

details

• Every computer or family of computers has its own

ML; each is machine-dependent

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Second Generation: Assembly

Languages • Represent a string of ‘0s’ and ‘1s’ for machine

language instruction

• More English-like; codes shorter than machine languages

• Assembler translates into machine language

• Advantages of machine or assembly languages

– Programmer in control of hardware

– Programs written in low-level languages run more efficiently

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Third Generation: Procedural

Languages

• Third-generation (procedural) languages are more English-like than assembly languages

• Programmers focus on the procedure of the application problem at hand

• Some languages are standardized or portable

• Relatively easy to learn, write, and debug

• FORTRAN, COBOL, BASIC

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Fourth Generation Languages (4GL)

• 4GLs are more English-like than procedural

languages

• Programmer only has to select an action without

having to specify the action’s formula or

procedure

• Easy to learn and use; shorter application

development time

• PowerBuilder, FOCUS, NOMAD, and RAMIS

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Fourth Generation Languages

(Cont.)

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Visual Programming

• Languages that let programmers create field

windows, scroll-down menus, click buttons,

etc., by choosing from a palette

• Appropriate code written automatically

• Accelerates work

• Examples: Microsoft’s Visual Basic, Visual

C++

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Object-Oriented Programming

(OOP)

• Emphasis on the objects involved in the task, not on the procedure

• An object encapsulates a data set with the code that is used to operate on it

• Standardized programming modules can be reused

• Applications can be rapidly developed with appropriate objects from an object library

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The object EMPLOYEE

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Programming Languages (Cont.)

– Levels of Programming Languages: Pluses

and Minuses

– Language Translation: Compilers and

Interpreters

• Source code

• Object code

• Compiler

• Interpreter

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Programming Languages (Cont.)

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Programming Languages (Cont.)

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Bugs

• Errors in a program to be eliminated before it

runs smoothly

• Occur when a certain operation cannot be

carried out

• Logic errors Vs. Syntax Errors

• Logic errors are most difficult to spot

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Application Software vs. System

Software

• Application:

– Program developed to address a specific

business need; software for development of

such programs

• System:

– Programs designed to carry out general

routine operations, such as loading, copying,

or deleting a file

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Application Software

• Application-specific programs

– Programs designed to perform specific jobs

• General-purpose programs

– Usable for different purposes

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Custom-Designed Application

Advantages

• Meeting the organization’s needs exactly

• In-house developers are sensitive to the

organizational culture

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Custom-Designed Application

Disadvantages

• High cost

• Production schedule subject to long delays

• Incompatible with other organizations’ systems

Management Information Systems, 4th Edition 24

Advantages and Disadvantages

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Packaged Software

• Advantages:

– Low cost

– High quality

– Vendor support

– Immediate availability

• Often tested at user sites (alpha sites and beta sites) before the final version is released

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Packages Software (Cont.)

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Packaged Software (Cont.)

• Word processors

• Electronic spreadsheets

• Database management systems

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Packaged Software (Cont.)

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Multimedia

• Can handle many different types of data such as

text, voice, and image

• Powerful means of communicating

• Uses include education, training, research, and

business

Management Information Systems, 4th Edition 30

Virtual Reality (VR)

• Mimics sensory reality

• Some sophisticated VR software includes use of

goggles, gloves, earphones, and a moving base

• Business use of VR is expected to grow

dramatically for design and testing of new

products, and for marketing

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System Software

• Manages computer resources and performs routine tasks not specific to any application

– Copying and pasting sections and files

– Printing documents

– Allocating memory

• Developed to partner with application software

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Operating Systems (O/S)

• Most important system software

– Developed for a certain microprocessor or

microprocessors

– Addresses technical details such as registers and

RAM addresses

– Plays the role of “traffic cop” or the “boss” of

computer resources

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Operating Systems (O/S) (Cont.)

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System Software

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Operating System Functions

• Systems Management

• User Interface

• Memory Allocation

• Multitasking, Multiprogramming, and Multiprocessing(multiprocessor)

• Times and Statistics

• Increasing Services from O/Ss

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Popular Operating Systems

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Data Communication Programs

• Controls and supports data communication

activities in a network

– Setting up rules that govern transmission and

reception of data

– Connecting and disconnecting communication

links

– Assigning priorities among terminals in a network

– Detecting and correcting transmission errors

Management Information Systems, 4th Edition 38

Linux and the Open Source

Revolution

• Proprietary software: source code of the

software public

• Open source software: source code can be

obtained free of charge

• Contains fewer bugs because thousands of

independent programmers review the code

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Considerations in Purchasing

Software

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Considerations in Purchasing

Software (Cont.)

Management Information Systems, 4th Edition 41

Summary

• Software developments and the impact on

business

• Application software versus operating system

software

• Tailored software versus off-the-shelf software

• Major developments in application and system

software

• Evaluation of package software