Management Information Systems, 3 rd Edition Effy Oz 1 Chapter 5 Information Systems in Business: Software

Management Information Systems, 3 rd Edition Effy Oz 2 Learning Objectives When you finish this chapter, you will: –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.

Management Information Systems, 3 rd Edition Effy Oz 3 Learning Objectives –Know the strengths and weaknesses of tailored software vs. off-the-shelf software. –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.

Management Information Systems, 3 rd Edition Effy Oz 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, 3 rd Edition Effy Oz 5 Programming Languages 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

Management Information Systems, 3 rd Edition Effy Oz 6 Programming Languages 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.

Management Information Systems, 3 rd Edition Effy Oz 7 Programming Languages 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.

Management Information Systems, 3 rd Edition Effy Oz 8 Programming Languages Procedural Languages –Third-generation (procedural) languages are more English-like than assembly languages. –Include FORTRAN, COBOL, BASIC –Programmers focus on the procedure of the application problem at hand. –Some languages are standardized or portable. –Relatively easy to learn, write, and debug.

Management Information Systems, 3 rd Edition Effy Oz 9 Programming Languages 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. –Include PowerBuilder, FOCUS, NOMAD, and RAMIS

Management Information Systems, 3 rd Edition Effy Oz 10 Programming Languages 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 –Microsoft’s Visual Basic

Management Information Systems, 3 rd Edition Effy Oz 11 Programming Languages 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

Management Information Systems, 3 rd Edition Effy Oz 12 Programming Languages Figure 5.3 Advantages of object-oriented programming (OOP) over procedural languages

Management Information Systems, 3 rd Edition Effy Oz 13 Programming Languages Figure 5.4 The object EMPLOYEE

Management Information Systems, 3 rd Edition Effy Oz 14 Programming Languages Figure 5.5 Advantages and disadvantages of higher- level programming languages

Management Information Systems, 3 rd Edition Effy Oz 15 Language Translation Compilers and Interpreters –Compiler 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

Management Information Systems, 3 rd Edition Effy Oz 16 Application Software Application –A program developed to address a specific business need; software for development of such programs. Application-specific software –Programs designed to perform specific jobs General-purpose application software –Usable for different purposes

Management Information Systems, 3 rd Edition Effy Oz 17 Application Software Custom-Designed or Tailored Software –Advantages: Meeting the organization’s needs exactly In-house developers are sensitive to the organizational culture Integration of special security measures Customized software maintenance –Disadvantages: High cost Production schedule subject to long delays Incompatible with other organizations’ systems

Management Information Systems, 3 rd Edition Effy Oz 18 Application Software Figure 5.7 Advantages and disadvantages of tailored applications

Management Information Systems, 3 rd Edition Effy Oz 19 Application Software Packaged Software –Advantages include: Low cost High quality Vendor support Immediate availability –Often tested at user sites (alpha sites and beta sites) before the final version is released Web browser is a popular ready-made application

Management Information Systems, 3 rd Edition Effy Oz 20 Application Software Figure 5.8 Advantages and disadvantages of packaged software

Management Information Systems, 3 rd Edition Effy Oz 21 Application Software Packaged Software –Word processors –Electronic spreadsheets –Database management systems

Management Information Systems, 3 rd Edition Effy Oz 22 Application Software Packaged Software –Web Browsers Necessary for accessing Web sites Main purpose is to view documents written in HTML, XML, Java, ActiveX, etc. –Web Page Authoring Tools Make Web composition easier and faster –Suites and OLE Integrated software

Management Information Systems, 3 rd Edition Effy Oz 23 Application Software Packaged Software –Hypermedia (Hypertext) First called Hypertext –The concept was limited to text Hypermedia enables linking of text, pictures, sounds, and animations

Management Information Systems, 3 rd Edition Effy Oz 24 Application Software 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, 3 rd Edition Effy Oz 25 Application Software 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

Management Information Systems, 3 rd Edition Effy Oz 26 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 as many applications as possible –Applications will work with system software ONLY if they are developed to be compatible

Management Information Systems, 3 rd Edition Effy Oz 27 System Software Operating Systems (O/S) –Single most important program and most important type of 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

Management Information Systems, 3 rd Edition Effy Oz 28 System Software Figure 5.10 The operating system mediates between applications and the computer, and controls peripheral devices.

Management Information Systems, 3 rd Edition Effy Oz 29 System Software Figure 5.11 Computers operate on a number of layers, starting from the user interface and moving inward to the hardware.

Management Information Systems, 3 rd Edition Effy Oz 30 System Software –Operating System Functions Systems Management User Interface Memory Allocation Multitasking, Multiprogramming, and Multiprocessing Times and Statistics Increasing Services from O/Ss

Management Information Systems, 3 rd Edition Effy Oz 31 System Software 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, 3 rd Edition Effy Oz 32 System Software Proprietary vs. Open Source –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.

Management Information Systems, 3 rd Edition Effy Oz 33 Considerations in Purchasing Software Figure 5.14 Sample results of software evaluation (5 is the highest score.)