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Managing Software Assets. Chapter Six. Software. Software : Detailed instructions that control the operation of a computer system. Program : Series of statements/instructions to the computer. Types of Software
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Managing Software Assets Chapter Six
Software • Software: Detailed instructions that control the operation of a computer system. • Program: Series of statements/instructions to the computer. • Types of Software • System software: Manages the computer’s resources & provides interface between hardware, software, and end user • Application software: Accomplishes a specific task, such as word processing Information Systems for Management
System Software #1 • Operating System • Allocates & assigns system resources • Schedules the use of computer resources & jobs • Monitors computer system activities • Multiprogramming permits multiple programs to share one computer’s resources (multitasking on single-user computer) • Multithreading executes different parts (threads) of a program simultaneously Information Systems for Management
System Software #2 • Virtual storage uses hard drive as part of primary memory • Pages are called up from the hard drive into memory while parts of what was in memory are placed back on the hard drive or erased from memory (paging) • Time sharing allows users to share computing resources simultaneously in slices of time • Multiprocessing links two or more CPUs to work in parallel on a program Information Systems for Management
System Software #3 • Programming Language Translation Software • Compiler translates source code into object code & executes the program at one time; result is a program in object code • Interpreter translates source code into object code & executes it one line at a time, allowing programmer to correct errors (bugs) as they are run; result is source code (no permanent object code) • Utility programs perform a variety of standard functions, such as copying and formatting Information Systems for Management
System Software #4 • Graphical User Interfaces: GUI • Windows • Icons • Mouse-clicks; click & drag • Menu or command driven interfaces Information Systems for Management
PC Operating Systems • Windows • XP Pro/2000/NT • XP Home/Me/98/95 • CE • OS/2 by IBM • Open source (Unix/Linux): stable, efficient, but hard-to-use because command driven • Mac OS • DOS (ancient): Still “under hood” of most Windows OS Information Systems for Management
Application Software #1 • Programming Languages • Generations • 1st: Machine (0’s & 1’s): binary • 2nd: Assembly language: specific to h/w/ & OS; use of commands (load, sum) & variable names (TOTAL) • 3rd: High-level languages: similar to English but syntax is hard for novices • FORTRAN • COBOL • BASIC • Pascal • C & C+ • C++ & other object-oriented languages transition to 4GLs Information Systems for Management
Application Software #2 • 4th: 4GL’s: Nonprocedural; closer to natural language • Query (SQL) • Report generator • Graphics • Application generator • Very high-level programming language Information Systems for Management
Application Software #3 • Packaged software: Prewritten, precoded, pretested, commercially available • PC Software Tools (office automation systems) • Word processing (MS Word) • Desktop publishing (MS Publisher) • Spreadsheet (MS Excel) • Database management (MS Access) • Presentation graphics (MS PowerPoint) • Integrated packages & Suites (MS Works vs. MS Office) • Email (MS Outlook) • Web browser (MS Internet Explorer) • Groupware (IBM’s LotusNotes) Information Systems for Management
Application Software #4 • Enterprise S/W (Enterprise Resource Planning or ERP) • Interdependent modules of applications for the functions of an enterprise (SAP or Peoplesoft) • Integrated data flows between modules • Implement one or more modules • Middleware interfaces between two different systems • Enterprise application integration software supports flow of information among different business units Information Systems for Management
S/W Development Tools • Object-oriented Programming • Combines data & specific procedures that operate on those data into one object • Visual programming uses a mouse to select & move “objects” to develop the program & dialogue boxes to develop most of the objects, procedures, and rules that govern the objects (e.g., Visual BASIC) • OOP Concepts • Classes: superclass, class, subclass (inheritance) Information Systems for Management
Modern Programming Languages #1 • Java • Platform-independent OOP language by Sun • Java applets downloaded from server to execute on client • Can handle multimedia & interactivity (Web pages) • MS developed ActiveX to compete with Java • OS independent • HTML (& its successors, DHTML, etc.) • Markup language (page description); use of tags • Incorporates hypertext links & hypertext/hypermedia documents • Can use a variety of packages to develop/edit HTML Information Systems for Management
Modern Programming Languages #2 • XML (eXtensible Markup Language) • Further development of HTML • Specifies how data will be used through XML tags, e.g., price, cost, etc. • Computers can automatically manipulate & interpret the data without human intervention • Need standards • XBRL (eXtensible Business Reporting Language) • Further development of HTML • Permits automatic manipulation & interpretation of financial reports Information Systems for Management
Make or Buy Decisions: ASPs • Application Service Providers • Provide apps via Internet or private network • Alternative to internal development • Cheaper (usually a “per seat” use) • Reduce IS staff • Guaranteed level of service Information Systems for Management
S/W Maintenance • Can take more than 50% of IS staff development time • Y2K Problem: Is it really over? Information Systems for Management
Selecting S/W • Appropriateness • User-friendliness • Efficiency • Cost • Compatibility • Hardware • OS • Other s/w • Support • Vendor reputation Information Systems for Management
Case Study: Sunburst Hotels • Why did Sunburst need an ERP? • Why did Sunburst decide to use an ASP? Information Systems for Management
Next Class • Chapter Seven: Managing Data Resources • Case Study: Ford & Firestone Information Systems for Management