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Chapter 5
Information Systems
in Business: Software
Management Information Systems, Second Edition
Effy Oz
Learning Objectives
 When you finish this chapter, you will:
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 Understand why managers must keep
abreast of software developments.
 Recognize the different generations of
programming languages and how they
differ.
 Understand the difference between
application software and system software.
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Learning Objectives
 Know the strengths and weaknesses of
tailored software vs. off-the-shelf software.
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 Be able to cite the latest major
developments in application and system
software.
 Recognize characteristics that are
important in evaluating packaged software
application for business use.
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Software: Instructions
to the Computer
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 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.
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Programming Languages
 Programming languages
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 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
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Figure 5.1
The evolution of
programming
languages
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Programming Languages
 Machine Languages (ML)
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 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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Programming Languages
 Assembly Languages
 Represents a string of ‘0s’ and ‘1s’ for a machine
language instruction
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 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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Programming Languages
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Figure 5.2 The instruction “ADD 2 and 5 and
assign the result to variable y” written in
different programming languages
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Programming Languages
 Procedural Languages
 Third-generation (procedural) languages are more
English-like than assembly languages.
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 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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Programming Languages
 Fourth Generation Languages (4GL)
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 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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Programming Languages
 Visual Programming
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 Languages that let programmers create
field windows, scroll-down menus, click
buttons, etc., by choosing from a palette
 Appropriate code written automatically
 Accelerates work
 Microsoft’s Visual Basic
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Programming Languages
 Object-Oriented Programming (OOP)
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 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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Programming Languages
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Figure 5.3 Advantages of object-oriented
programming (OOP) over procedural languages
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Programming Languages
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Figure 5.4 The object EMPLOYEE
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Programming Languages
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Figure 5.5 Advantages and disadvantages of higherlevel programming languages
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Programming Languages
 Application Software vs. System Software
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 Application: a 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
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 Programs designed to perform specific
jobs
 General-purpose programs
 Usable for different purposes
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Application Software
 Custom-Designed Applications
 Advantages:
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 Meeting the organization’s needs exactly
 In-house developers are sensitive to the
organizational culture
 Disadvantages:
 High cost
 Production schedule subject to long delays
 Incompatible with other organizations’ systems
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Application Software
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Figure 5.6 Advantages and disadvantages of tailored
applications
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Application Software
 Packaged Software
 Advantages:
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



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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Application Software
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Figure 5.7 Advantages and disadvantages of
packaged software
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Applications Software
 Packaged Software
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 Word processors
 Electronic spreadsheets
 Database management systems
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Packaged Software
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Figure 5.8 Electronic
spreadsheets are
powerful tools for (a)
tabulation, (b)
manipulation, and (c)
data analysis.
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Packaged Software
 Multimedia
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 Can handle many different types of data
such as text, voice, and image.
 Powerful means of communicating.
 Uses include education, training, research,
and business.
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Packaged Software
 Virtual Reality (VR)
 Mimics sensory reality.
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 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
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 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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System Software
 Operating Systems (O/S)
 Most important system software
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 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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System Software
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Figure 5.9 The operating system mediates between
applications and the computer, and controls
peripheral devices.
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System Software
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Figure 5.10 Computers operate on a number of layers,
starting from the user interface and moving inward to
the hardware.
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System Software
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Figure 5.11 Popular operating systems
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System Software
 Operating System Functions
 Systems Management
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 User Interface
 Memory Allocation
 Multitasking, Multiprogramming, and
Multiprocessing
 Times and Statistics
 Increasing Services from O/Ss
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System Software
 Compilers and Interpreters
 Compiler
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 Scans source code and translates into object
code
 Generates error message and does not compile
when an error is found
 Allows users to save programs in object code
 Interpreter
 Checks one statement at a time
 Changes error-free statements into ML
 Generates an error message for errors
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System Software
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Figure 5.12 A compiler converts higher-level
language code (source code) into machine
language (object code), which the computer
can process.
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System Software
 Data Communication Programs
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 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
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System Software
 Proprietary vs. Open Source
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 Proprietary O/S: limited to using applications
compatible with it
 Open O/S: compatible with virtually all
applications.
 Completely open O/S does not exist
 Some O/Ss (e.g., Unix) are said to be
nonproprietary, but it is still impossible to run
many applications on different versions of
such O/Ss.
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Considerations in
Purchasing Software
Figure 5.13 Sample
software evaluation
form
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Considerations in
Purchasing Software
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Figure 5.14 Sample results of software evaluation (5 is the
highest score.)
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The Year 2000 Problem
 Many business applications stored only
the last two digits of year dates.
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 If no corrective action taken, businesses
might have experienced chaos on
January 1, 2000.
 ISs interpreting 00 as 1900 instead of 2000
 Experts predict the Y2K bug will haunt
many organizations several years after
2000.
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