1. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 1 Managing Information Technology CHAPTER 3 COMPUTER SOFTWARE

2. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 2 Building Blocks of Information Technology HardwareSoftwareNetworkData

3. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 3 EVOLUTION OF COMPUTER PROGRAMMING Machine language (1GL) – Each instruction must be expressed in unique form for a particular computer – Complete program consists of thousands of instructions – Programming is a tedious, time-consuming process Assembly languages (2GL) – Easily remembered mnemonic operation codes substituted for machine language operation codes – Assembler used to convert mnemonic codes to machine language First and Second Generation Languages

4. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 4 EVOLUTION OF COMPUTER PROGRAMMING First and Second Generation Languages

5. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 5 EVOLUTION OF COMPUTER PROGRAMMING Procedural languages (3GL) – Typically machine independent – Express a step-by-step procedure devised by the programmer – Must be compiled or interpreted (translated into machine language) – Include FORTRAN, COBOL, BASIC, PL/1, PASCAL, ADA, and C Third and Fourth Generation Languages

6. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 6 EVOLUTION OF COMPUTER PROGRAMMING Third and Fourth Generation Languages

7. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 7 EVOLUTION OF COMPUTER PROGRAMMING Nonprocedural languages (4GL) – Also referred to as productivity languages – Use more English-like statements for program instructions – Easier to use, write, and less error-prone – Use a built-in interpreter to convert to machine language – Take much longer to execute than 3GLs – Include FOCUS, CA-Ramis, IFPS, and SAS Third and Fourth Generation Languages

8. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 8 EVOLUTION OF COMPUTER PROGRAMMING Third and Fourth Generation Languages

9. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 9 EVOLUTION OF COMPUTER PROGRAMMING Object-oriented languages – 3GLs with some 4GL features – Built on idea of embedding procedures (methods) in objects, and putting objects together to create an application – Include Smalltalk, C++, Java, and Visual Basic Third and Fourth Generation Languages

10. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 10 KEY TYPES OF SOFTWARE 1.Applications software 2.Support software

11. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 11 APPLICATIONS SOFTWARE Programs written to accomplish particular tasks Many different types of applications software Standard applications products generally purchased from an outside source Applications unique to the organization generally developed internally Personal productivity software most important to managers

12. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 12 APPLICATIONS SOFTWARE Peachtree accounting software – Commercial accounting package for smaller businesses – Includes general ledger, accounts receivable, accounts payable, inventory, payroll, time and billing, job costing, fixed asset accounting, and analysis and reporting tools – $500 for single-user version Examples of Application Software

13. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 13 APPLICATIONS SOFTWARE Sage Accpac 200 ERP – Modular financial management systems for midsized businesses – Web-based, so only a Web browser is needed to access the application – System Manager module manages security, ensures data integrity, handles bank reconciliation and tax processing, and allows for customized reports – Several other modules available as well Examples of Application Software

14. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 14 APPLICATIONS SOFTWARE Word processing – Used to create documents for printing – Most popular is Microsoft Word – Others include Corel WordPerfect, Lotus WordPro, and Sun’s StarOffice Writer – All employ WYSIWYG Personal Productivity Software

15. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 15 APPLICATIONS SOFTWARE Spreadsheets – Used to create applications that fit a row-column format – Most popular is Microsoft Excel – Others include Lotus 1-2-3 and Corel Quattro Pro – All employ rows, columns, cells, formulas, and “what-if” analysis Personal Productivity Software

16. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 16 APPLICATIONS SOFTWARE Database management systems – Used to create databases similar to those on larger machines – Most popular is Microsoft Access – Others include FileMaker Pro, Corel Paradox, and Lotus Approach – All employ a relational data model Personal Productivity Software

17. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 17 APPLICATIONS SOFTWARE Presentation graphics – Used to create largely textual business presentations – Most popular is Microsoft PowerPoint – Others include Corel Presentations and Lotus Freelance Graphics – All allow embedding of clip art, photos, graphs, and other media Personal Productivity Software

18. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 18 APPLICATIONS SOFTWARE Web browsers – Used to access information on the Web – Requires ISP service to link PC to Internet – Create documents for printing – Most popular are Internet Explorer and Firefox… both free! – Both employ standard hypertext-based approach (way to link text and media objects to each other) – Pull technology: browser requests a Web page before it is sent to desktop – Push technology: data sent to client without requesting it (such as e-mail) Personal Productivity Software

19. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 19 APPLICATIONS SOFTWARE Electronic mail – Preferred way of communicating in business today – Easy to use and precise Groupware – Incorporates e-mail and other productivity features, such as calendaring, scheduling, and document sharing Personal Productivity Software

20. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 20 SUPPORT SOFTWARE Provides computing environment that is easy and efficient for humans to use Enables applications programs to be carried out Ensures that computer hardware and software are used efficiently Almost always purchased from a hardware vendor or software house

21. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 21 SUPPORT SOFTWARE Most important type of support software Complex program that controls operation of computer hardware and coordinates other software User communicates with operating system software to control hardware and software resources Communication made easier with a graphical user interface (GUI) feature Operating System

22. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 22 SUPPORT SOFTWARE Operating System

23. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 23 SUPPORT SOFTWARE Job control language (JCL): keyed instructions from the computer user to communicate with the operating system Multiprogramming: employed on larger machines to overlap input and output operations with processing time, keeping the CPU busy and speeding up execution Multitasking: similar to multiprogramming, but employed on microcomputers Multithreading: similar to multitasking, but multiple threads within the same program are overlapped Operating System

24. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 24 SUPPORT SOFTWARE Virtual Memory: – Concerned with management of main memory – Makes it appear that an unlimited amount of memory is available – Permits multiprogramming to operate more efficiently Multiprocessing: work that takes place when two or more CPUs are installed on same computer system Operating System

25. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 25 SUPPORT SOFTWARE Sources of operating systems – Proprietary systems: most popular type of operating systems, written for a particular computer hardware configuration Microcomputers: MS-DOS, PC-DOS, Windows XP Midrange systems: OS/400 Large systems: VM and MVS – Open systems: not tied to any particular computer system or hardware manufacturer – will run on virtually any computer system Examples: UNIX and Linux Operating System

26. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 26 SUPPORT SOFTWARE Network operating systems (NOS) – Software running on a server that manages network resources and controls the operation of a network – Enhanced operating system that allows for: Sharing disk drives and printers Handling server side of client/server applications – Major players include: UNIX and Linux Microsoft Windows NT, 2000 Server, 2003 Server Novell NetWare Operating System

27. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 27 SUPPORT SOFTWARE Procedural languages (3GL) – Require logical thinking – Entail development of a detailed step-by-step procedure – Can be developed using structured programming Third Generation Languages

28. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 28 SUPPORT SOFTWARE Third Generation Languages

29. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 29 SUPPORT SOFTWARE Structured programs – Divided into modules, where each has one entry and one exit point – Advantages Program logic easier to follow Maintenance and correction easier and faster Do not use GO TO logic Third Generation Languages

30. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 30 SUPPORT SOFTWARE Most popular procedural languages – BASIC – C – COBOL Other procedural languages – FORTRAN – PL/1 – PASCAL – ADA Third Generation Languages

31. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 31 SUPPORT SOFTWARE Third Generation Languages - BASIC

32. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 32 SUPPORT SOFTWARE Third Generation Languages - COBOL

33. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 33 SUPPORT SOFTWARE Nonprocedural languages – Use very high-level instructions – Require fewer instructions – Easier to write, modify, and understand – Example: FOCUS Fourth Generation Languages

34. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 34 SUPPORT SOFTWARE Fourth Generation Languages - FOCUS

35. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 35 SUPPORT SOFTWARE Employ tags to “mark up” documents HTML – Used to create Web pages – Consists of special tags that tell the Web browser how to display various elements on a Web page (e.g., bold-faced or italic text, image location, links to other Web pages) XML – Used to facilitate data interchange among Web applications – Metalanguage consisting of tags that identify particular data elements Markup Languages

36. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 36 SUPPORT SOFTWARE Requires more computing power Has built-in GUI Neither 3GL nor 4GL … new paradigm Creates objects only once and stores for reuse Object examples: – Text box, check box, entity in an organization Languages: – Smalltalk, C++, Java, Visual Basic.NET Object-Oriented Programming

37. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 37 SUPPORT SOFTWARE Object-Oriented Programming - Java

38. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 38 SUPPORT SOFTWARE HTML form is the most common user interface encountered by users Server-side programming languages include: – Perl – Java Servlets and Java Server Pages – Microsoft Active Server Pages (ASP, ASP.NET) – ColdFusion Languages for Developing Web Applications

39. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 39 SUPPORT SOFTWARE Languages for Developing Web Applications

40. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 40 SUPPORT SOFTWARE Support software used to create, manage, and protect organizational data Database: shared collection of logically related data organized to meet organizational needs Five basic architectures: 1.Hierarchical Data are arranged in a top-down organization chart fashion Example: IBM Information Management System (IMS) Database Management Systems

41. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 41 SUPPORT SOFTWARE Five basic architectures: 2.Network Data are arranged like cities on a highway system, often with several paths from one piece of data to another Example: Computer Associates Advantage CA-IDMS 3.Relational Most common type Data arranged in simple tables Records related by storing common data in each associated table Examples: Microsoft Access and SQL Server, Paradox, DB2, and Ingres Database Management Systems

42. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 42 SUPPORT SOFTWARE Five basic architectures: 4.Object-oriented Data can be graphics, video, and sound as well as simpler data types Attributes and methods are encapsulated in object classes, and relationships between classes can be shown by nesting one class within another Examples: Versant Object Database, Progress ObjectStore, and Objectivity/DB 5.Object-relational Hybrid approach that can handle complex data types with the simplicity of the relational model Examples: Oracle, IBM’s DB2 and Cloudscape, and FFE Software’s FirstSQL/J Database Management Systems

43. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 43 SUPPORT SOFTWARE Sequential: arranges records physically adjacent and in order by some (usually unique) sort key Direct: uses key for records placed so that they are rapidly accessed from DASDs File Organizations

44. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 44 SUPPORT SOFTWARE Indexed – Compromise between sequential and direct – Record keys only arranged in sequence in a separate table, along with location of rest of data associated with that key – Popular types include ISAM and VSAM File Organizations

45. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 45 SUPPORT SOFTWARE Computer-aided software engineering (CASE) Collection of software tools to help automate all phases of the software development life cycle Growth slower than anticipated Radically changed nature of systems analyst and programmer jobs CASE Tools

46. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 46 SUPPORT SOFTWARE Recent surge in CASE tools for Unified Modeling Language (UML) – UML is a general-purpose notational language for specifying and visualizing complex software, especially large, object-oriented projects – Examples of UML-base CASE tools IBM’s Rational Rose Borland’s Together Sybase’s PowerDesigner CASE Tools

47. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 47 SUPPORT SOFTWARE Large computers – Need to control workstations and terminals – Example software: IBM’s CICS, TSO, and CMS Increasingly important with growth of LANs and WANs Web browsers: enable users to look around, or “browse,” the Internet Telnet: permits user to log into remote computer File Transfer Protocol (FTP): used to transfer files from one computer system to another Communications Interface Software

48. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 48 THE CHANGING NATURE OF SOFTWARE Less concern with machine efficiency More purchased applications, and, conversely, more use of open source support software, such as Linux More programming using object-oriented languages More emphasis on applications that run on intranets and the Internet More user development More use of personal productivity software on microcomputers

49. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall 49 THE SOFTWARE COMPONENT OF THE INFORMATION SYSTEMS INDUSTRY Hardware manufacturers – IBM, Hewlett-Packard, Sun Microsystems, Hitachi, and Fujitsu Software houses – Microsoft, Oracle, SAP, Computer Associates, and Symantec Consulting firms – PricewaterhouseCoopers Consulting (bought by IBM) Major Groups