1. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. McGraw-Hill Chapter 05: System Software

2. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-2 McGraw-Hill Definition of OS/System Software Master programMaster program Controls all hardwares connected to computerControls all hardwares connected to computer Collection of programsCollection of programs Users Application software Operating System/ system software Hardware

3. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-3 McGraw-Hill System Software Handles the technical detailsHandles the technical details –Includes the operating system, utilities, device drivers, and language translators

4. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-4 McGraw-Hill Operating Systems A collection of programs that handle technical tasks, including managing computer resourcesA collection of programs that handle technical tasks, including managing computer resources Every computer has an operating system (OS), such as Windows 7 or Mac OS XEvery computer has an operating system (OS), such as Windows 7 or Mac OS X The OS provides the interface between the user and computer, and is required to run applicationsThe OS provides the interface between the user and computer, and is required to run applications

5. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-5 McGraw-Hill Examples

6. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-6 McGraw-Hill Functions of an Operating System Manages computer resourcesManages computer resources –Control Processor, Memory, storage and all hardwares –Control system performance –Provide security Provides user interfaceProvides user interface –Character-based interface –Graphical user interface (GUI) Runs applicationsRuns applications –Multitasking –Foreground and background applications

7. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-7 McGraw-Hill Layers of System Software

8. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-8 McGraw-Hill BIOS Basic input/output system, the built-in software runs first when you switch on computer It performs POST( Power On Self Test) It identifies devices connected to computer

9. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-9 McGraw-Hill

10. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-10 McGraw-Hill Booting Booting is the process of bringing OS from Hard disk to RAMBooting is the process of bringing OS from Hard disk to RAM

11. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-11 McGraw-Hill Categories of Operating Systems Hundreds of operating systemsHundreds of operating systems Three basic categoriesThree basic categories –Embedded operating systems (handheld) –Network operating systems (linked computers) –Stand-alone operating systems (desktop)

12. Copyright © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Computing Essentials 2012: Making IT Work for You 5-12 McGraw-Hill Storage Hierarchy Very fast storage is very expensive. So the Operating System manages a hierarchy of storage devices in order to make the best use of resources. In fact, considerable effort goes into this support. 1: Operating Systems Overview12 Fast and Expensive Slow an Cheap