Chapter 4TopicsProcessing with ProgramsFood for ThoughtA Fast, Stupid MachineSlide 6The Language of ComputersSoftware Applications: Tools for UsersConsumer ApplicationsDocumentationUpgradesCompatibilityDisclaimersLicensingDistributionIntegrated Applications and Suites: Software BundlesIntegrated Software: AdvantagesVertical-Market and Custom SoftwareSystem Software: The Hardware-Software ConnectionWhat the Operating System DoesUtility ProgramsWhere the Operating System LivesThe User Interface: The Human-Machine ConnectionA Character-Based Interface: MS-DOSSlide 25Graphical User Interfaces: MacintoshGraphical User Interfaces: WindowsWhy WIMP WonMultiple User Operating Systems: UNIX and LinuxSlide 30Hardware & Software PlatformsTomorrow’s User InterfacesSlide 36 2002 Prentice HallChapter 4Software Basics:The Ghost in the Machine 2002 Prentice Hall 2 TopicsProcessing with ProgramsSoftware Applications: Tools for UsersSystem Software: The Hardware-Software ConnectionThe User Interface: The Human-Machine ConnectionTomorrow’s User Interfaces 2002 Prentice Hall 3 Processing with ProgramsSoftware programs are:Stored in memoryInstructions that tell the computer what to do Designed to solve problemsLeonardo da Vinci called music ”the shaping of the invisible,“ and his phrase is even more apt as a description of software.—Alan Kay, developer of the concept of the personal computer 2002 Prentice Hall 4 Food for Thought1. Combine 2 slightly beaten eggs with 1 tsp vanilla extract, ½ tsp cinnamon, 1 cup milk2. Dip 6 slices of bread in mixture3. Fry in small amount of butter until golden brown4. Serve bread with maple syrup, sugar, or tart jellySuzanne’s French Toast Fantastique: 2002 Prentice Hall 5 A Fast, Stupid MachineComputers:Perform arithmetic and comparisons capabilitiesFollow precise instructions to perform an operationExecute instructions quickly and accurately 2002 Prentice Hall 6 A Fast, Stupid MachineProgrammers begin with an algorithm An algorithm is:A set of step-by-step instructions (written in a natural language, e.g., English)Algorithms are ambiguous, error-prone generalitiesAlgorithms are translated into the vocabulary of a programming language 2002 Prentice Hall 7 The Language of ComputersMachine Language numeric codes to represent dataHigh-level language fall between machine language and natural human languageCompilers translates high-level language into Natural Languages include the languages spoken by humans 2002 Prentice Hall 8 Software Applications:Tools for UsersSoftware applications include:Consumer ApplicationsIntegrated SoftwareVertical-marketCustom Software 2002 Prentice Hall 9 Consumer Applications•Consumer software differs from other types (music CDs, videos, etc.) based on:DocumentationUpgrade optionsCompatibilityWarrantyExtent of ownership/license 2002 Prentice Hall 10 DocumentationDocumentation includes:Printed tutorial and reference manuals that explain how to use the softwareOn-line manuals and help screens which offer immediate help to the user 2002 Prentice Hall 11 Upgrades allow you to pay a fee to get the latest software version Newer releases often have additional features and fewer bugsUpgrades 2002 Prentice Hall 12 CompatibilityCompatibility allows software to function properly with the hardware, operating system, and peripheralsPrograms written for one type of computer system may not work on another 2002 Prentice Hall 13 DisclaimersSoftware manufacturers limit their liability for software problems by selling software “as is”Given the difficulty of this task, most programs work amazingly well—but not perfectly 2002 Prentice Hall 14 LicensingLicensing agreements limit your right to:Make copies of software disks install software on hard drivestransfer information to other users Commercial software is copyrighted so it can’t be legally duplicated for distribution to others. 2002 Prentice Hall 15 DistributionSoftware is distributed through direct sales forces to corporations and other institutions.Software is sold to consumers through:retail stores mail-order catalogsWeb sites. 2002 Prentice Hall 16 Integrated Applications and Suites: Software BundlesMultipurpose software includes most of these modules:Word processingDatabaseSpreadsheetGraphicsTelecommunications 2002 Prentice Hall 17 Integrated Software: AdvantagesCosts less than buying the applications individuallyData is easily transferred between modulesCommands used in each module are usually the sameUsually there is a seamless integration of the modules 2002 Prentice Hall 18 Vertical-Market andCustom SoftwareJob-specific software:Medical billingsLibrary catalogingRestaurant managementSingle-client software needs 2002 Prentice Hall 19 System Software: The Hardware-Software ConnectionSystem software is a class of software that includes:The operating systemUtility programs 2002 Prentice Hall 20 What the Operating System DoesThe operating system controls:Communication with peripheralsCoordination of concurrent processingMemory managementMonitoring of resources and securityManagement of programs and dataCoordinating network communications 2002 Prentice Hall 21 Utility Programs Upgrades allow you to pay a fee to get the latest software version translating files so different software can read themguarding against virusesrepairing damaged filescopying files from one storage device to another 2002 Prentice Hall 22 Where the Operating System LivesSome computers store their operating system in ROM Others include only part of it in ROMThe remaining system is loaded into memory (booting) Most of the time it works behind the scenes 2002 Prentice Hall 23 The User Interface: The Human-Machine Connection The user interface is what the user sees on the screen Two major user interface types:Character-based interfaceGraphical user interface (GUI) 2002 Prentice Hall 24 A Character-Based Interface: MS-DOSThis is a disk operating system in which the user interacts using