1. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 1 Third Edition Chapter 1 Introduction to Operating Systems McGraw-Hill

2. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 2 Learning Objectives LO 1.1Describe the purpose and functions of operating systems LO 1.2Describe major events in the evolution of operating systems LO 1.3List and compare the common operating systems in use today

3. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 3 An Overview of Operating Systems What is a Microcomputer? – A computer built around a microprocessor Microprocessor is a special integrated circuit (IC) that performs calculations and processing An IC (chip) is a small electronic component made up of transistors and other miniaturized parts Microprocessor also called central processing unit (CPU) Many other ICs in a computer

4. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 4 A typical PC with components

5. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 5 An Overview of Operating Systems What’s Inside a Microcomputer? – A least one CPU – Motherboard – RAM – ROM BIOS – Also attached Keyboard Display Printer Pointing Device and much more

6. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 6 An Overview of Operating Systems What’s Inside a Microcomputer? – More About ROM BIOS Program code for basic control of devices Many components contain additional ROM BIOS Device drivers install in OS for each device ROM BIOS includes power-on-self test (POST)

7. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 7 Figure 1-1 An example of a BIOS start-up message

8. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 8 An Overview of Operating Systems What’s Types of Microcomputers are in Use Today? – Desktops and Laptops – Servers – Handheld Devices Growing number and types Most popular are smartphones (iPhone, BlackBerry, etc.)

9. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 9 A PC laptop

10. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 10 Two MacBook laptops

11. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 11 An Overview of Operating Systems Functions of Operating Systems – An Operating System is: The central control program(s) for a computer Loads when computer is turned on Kernel (main component) remains in memory – Manages low-level OS tasks – Acts as intermediary between applications & hardware

12. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 12 An Overview of Operating Systems Functions of Operating Systems – User interface – Job management – Task management – Memory Management – File management – Device management – Security

13. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 13 The functions of an operating system

14. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 14 An Overview of Operating Systems User Interface – A software layer for user interaction – Includes the command processor – Includes the visual components of the OS Character-based command line GUI

15. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 15 Figure 1-2 MS-DOS prompt

16. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 16 Figure 1-3 A typical GUI screen

17. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 17 An Overview of Operating Systems Job management – Controls the order and time in which programs are run Task management – Found in multitasking operating systems – Controls the focus – Allows user to switch between tasks

18. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 18 An Overview of Operating Systems Memory Management – Manages placement of programs and data in memory – Virtual memory manager moves code and data to virtual memory (file on hard drive)

19. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 19 An Overview of Operating Systems File Management – AKA data management – Allows the OS to read, write, and modify data – Data is organized into files – Allows users to organize their files into containers called folders or directories

20. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 20 An Overview of Operating Systems Device Management – Controls hardware through device drivers – A device driver is unique to a device – Created by the manufacturer of the device to work with a specific operating system

21. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 21 An Overview of Operating Systems Security – Provides password-protected authentication of the user before allowing access – Checks user name and password – Restricts the actions that can be performed on a computer, customized for each user

22. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 22 An Overview of Operating Systems Categories of Operating Systems – Single-User/Single-tasking – Single-User/Multitasking – Multi-User/Multitasking – Real-Time – 16-, 32-, and 64-bit OSs

23. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 23 Figure 1-4 Single-user/single-tasking

24. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 24 Figure 1-5 Single-user/multitasking

25. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 25 Figure 1-6 Multiuser/multitasking

26. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 26 Figure 1-7 Example of a device containing a real-time embedded system

27. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 27 Yesterday’s Operating Systems UNIX–The OS for All Platforms – 1975: UNIX version 6 emerged from Bell Labs Computing Science Research Center (Bell Labs) – OS for many platforms – Free versions: BSD, Net BSD, Open BDS, & Open Solaris. Commercial versions: AIX, OpenServer (derived from SCO UNIX), & HP/UX – Traditional CLI shell – GNOME and KDE GUIs

28. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 28 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Apple OS for Apple I and Apple II (non-GUI) 1976: Steve Jobs created Apple I and founded Apple Computer 1977: Apple introduces Apple II at the West Coast Computer Faire in San Francisco 1978: Added disk drives for Apple II – GUI Apple OSs 1982: Apple Lisa computer 1984: Macintosh computer

29. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 29 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – GUI Apple OSs (cont.) 1999: Mac OS 9 – Multi-user – Weak in memory management and multitasking 2001: Mac OS X – First Mac OS based on UNIX – Has both a GUI and a CLI

30. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 30 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – MS-DOS 1981: IBM-PC with PC-DOS by Microsoft Single-tasking with very limited memory support No native GUI No built-in security functions Microsoft developed several versions of MS-DOS

31. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 31 Figure 1-9 MS-DOS prompt with the Format command

32. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 32 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – OS/2 (Operating System/2) 1987: Version 1.0 introduced Developed by Microsoft and IBM 1.0 had costly memory and disk requirements 1990’s: IBM introduced OS/2 Warp mainly for servers 2003: IBM ended development of new versions 2004: IBM sold PC division to China-based Lenovo Group

33. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 33 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Microsoft Windows Version is a new level of Windows OS Edition is a unique product based on a version (several editions per version) 1985: Windows 1 – a GUI on top of DOS 1990: Windows 3.0 provided better support for legacy DOS applications 1992: Windows 3.1 successful with MS Office

34. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 34 Figure 1-10 Windows 3.1 desktop

35. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 35 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Windows for Workgroups DOS and earlier versions of Windows had no built-in network support 1992: Windows for Workgroups 3.1 and 3.11 enabled peer-to-peer networking Still dependent on DOS

36. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 36 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Windows NT 1993: First Microsoft OS to take full advantage of the capabilities of the Intel 386 protected mode Two main versions of NT – one for servers and another for desktop computers 1996: Windows NT 4.0 with a GUI similar to Windows 95 Microsoft no longer sells or supports Windows NT

37. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 37 Figure 1-11 Windows NT 4.0 desktop with open windows

38. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 38 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Windows 95 1995: Windows 95 introduced; predated Windows NT Workstation A continuation of the Windows 3.X model: GUI on top of DOS Both 16-bit and 32-bit code A new GUI

39. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 39 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Windows 98 1998: An upgrade to Windows 95 More stable Greater integration with Internet Explorer More customization options Support for new devices like DVD drives Drawback: Lacked local security

40. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 40 Figure 1-12 MS Windows 98 desktop with open windows

41. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 41 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Windows Me 2000: An upgrade to Windows 98 Improved music, video, and home networking support Provided both utilities and applications for dealing with PC software configuration, digital music, and video

42. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 42 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Windows 2000 Windows 2000: Introduced in several editions – Windows 2000 Professional (for desktops and laptops) – Windows 2000 Server – Windows 2000 Advanced Server – Windows 2000 Enterprise Edition Combines the best of Windows 98 and Windows NT

43. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 43 Figure 1-13 MS Windows 2000 desktop

44. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 44 Yesterday’s Operating Systems The Evolution of Microcomputer OSs (cont.) – Windows XP 2001: Several editions, but no server version Most common: – Windows XP Home Edition – Windows XP Professional (enhanced security features) – Windows XP Media Edition Most editions were 32-bit Windows XP 64-bit Edition for Intel Itanium processor platform Support life cycle for XP is ending

45. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 45 Figure 1-14 MS Windows XP desktop with open windows

46. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 46 Table 1-2: Summary of Current Desktop OSs Today’s Desktop OSs

47. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 47 Today’s Desktop OSs Windows Vista – 2007: A new GUI, other improvements – But not widely adopted

48. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 48 Figure 1-15 The Windows Vista desktop

49. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 49 Today’s Desktop OSs Windows 7 – Improvements that solved problems with Vista

50. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 50 Figure 1-16: The Windows 7 desktop

51. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 51 Today’s Desktop OSs Windows 8

52. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 52 Today’s Desktop OSs Windows File Systems – FAT file systems FAT12, FAT16, FAT32, exFAT Logical structure includes file allocation table and special files called directories – NTFS Introduced in Windows NT In subsequent Windows except Windows 9x and Windows Me Supports very large disk volumes and security

53. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 53 Today’s Desktop OSs Windows File Systems – File systems for optical drives CD-ROM File System (CDFS) Universal disk Format (UDF) Live File System

54. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 54 Today’s Desktop OSs Mac OS X – Now Mac OS X is only licensed to run on Apple computers

55. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 55 Figure 1-17 Mac OS X GUI

56. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 56 Today’s Desktop OSs Linux – Modeled on UNIX – Named for original developer, Linus Benedict Torvalds – Begun in 1991 by Torvalds and others as open-source for modern computers – Written in the C language using the GNU C Compiler (GCC)

57. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 57 Today’s Desktop OSs Linux (cont.) – Available in both 32-bit and 64-bit distributions – Multitasking / multi-user – Novell, Red Hat, and others distribute such bundles – Fastest-growing computer server OS – Supports several file systems Old Minux, ext, ext2 Journaling in ext3, ReiserFS, JFS, XFS

58. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 58 Figure 1-18 Red Hat Linux directory listing (ls command)

59. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 59 Chapter 1 Summary LO1.1An Overview of Operating Systems – A computer consists of hardware and two types of software: operating system software and applications software. – The operating system allows the user to interact with the computer hardware. – Certain computer hardware is common to most computers. The basic components include the processor, motherboard, RAM, ROM BIOS, video adapter, display screen, keyboard, pointing device, and other peripherals.

60. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 60 Chapter 1 Summary LO1.1An Overview of Operating Systems (cont.) – Common computers in use today include desktops, laptops, server systems, and handheld devices. – Most, if not all, current operating systems provide a user interface, job management, task manage- ment, memory management, file management, device management, and security. – There are four categories of operating systems: single-user / single-tasking, single-user / multi- tasking, multiuser/multitasking, and real-time.

61. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 61 Chapter 1 Summary LO1.1An Overview of Operating Systems (cont.) – Today’s popular operating systems for desktops and laptops come in versions for 32-bit and 64-bit processing. The biggest advantage of a 64-bit OS over a 32-bit version of the same OS is that the amount of memory supported is much greater in a 64-bit OS.

62. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 62 Chapter 1 Summary LO 1.2Yesterday’s Operating Systems – The history of current computers and their OSs involved many technical advances and the imagination of a multitude of innovative people. – UNIX is the oldest popular operating system and comes in versions for very large computers

63. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 63 Chapter 1 Summary LO 1.2Yesterday’s Operating Systems (cont.) – Early microcomputers included the MITS Altair 8800, the Apple I and Apple II, Radio Shack’s TRS-80, and the Commodore, all introduced in the 1970s. The Apple computers came with the Apple OS.

64. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 64 Chapter 1 Summary LO 1.2Yesterday’s Operating Systems (cont.) – IBM introduced the PC in 1981, and it far exceeded the expectations of IBM with Microsoft BASIC in ROM and PC DOS for computers with a floppy disk drive. – Microsoft made MS-DOS available to third-party PC manufacturers. – Microsoft Windows evolved from the first version in 1985 to Windows 7, introduced in 2009.

65. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 65 Chapter 1 Summary LO 1.2Yesterday’s Operating Systems (cont.) – The Apple Mac computer, introduced in 1984, came with the MAC OS System. This OS line continued through Mac OS 9, introduced in 1999, and phased out after Mac OS X was introduced 2001

66. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 66 Chapter 1 Summary LO 1.3Today’s Desktop Operating Systems – The operating systems common today include Windows XP, Windows Vista, Windows 7, Mac OS X, and Linux. – Windows supports several file systems for hard drives and optical disks. The most feature-rich and secure file system for hard drives is the NTFS file system.

67. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 67 Chapter 1 Summary LO 1.3Today’s Desktop Operating Systems (cont.) – Mac OS X, based on NextStep, an OS with a UNIX kernel, runs only on Apple Macintosh computers, – Linus Torvalds developed Linux as a collaborative effort beginning in 1991. A full multitasking / multiuser operating system, it is available in both 32-bit and 64-bit distributions and can run on nearly any computer.

68. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. 68 Chapter 1 Summary LO 1.3Today’s Desktop Operating Systems (cont.) – Linux supports several file systems for hard drives and optical disks.