Elementary Computing CSC 100. M. Cheng, Computer Science

Transcription

1 Elementary Computing CSC 100 1

2 File & Operating Systems Every computer has an Operating System (OS). An OS is a piece of software that manages the resources on every computer. User Interfaces and File Systems are two of the most visible components of an OS. A File System (FS) helps us managing our data on storage. 2

3 Outcomes An OS is an essential piece of software for any computer. A File System gives us a structured and hierarchical view of our data files. A File System has additional security features to prevent unauthorized accesses. Multitasking enables us to run many applications at once. 3

4 Study Guide What is an Operating System (OS)? What typical tasks an OS automate? What does an OS do exactly? What is a command line interface or GUI? What are the examples of an modern OS? What is the layered structure of a computer? What are the most important components of an OS? 4

5 Study Guide What are primary and secondary storage? What does formatting a hard disk mean? What are the common File Systems? What is a File System? What are files and folders, and pathname? What are file and folder permissions? What is multitasking? 5

6 What is an Operating System? 6

7 Historically, computers are too complicated for an average user to operate. 7

8 Inside a Desktop Computer 8

9 Typical tasks an OS do Control the graphic display Connect to the network Send documents to a printer Back up our data onto a hard disk Control your keyboard / mouse Share data among computers Start up / shut down a computer 9

10 An OS takes care of An OS automates many of the hardware specific operations. It knows how to set up the wireless network. It knows how to communicate with a printer. It knows how to store and retrieve data on your hard drives. It knows how to display graphics and fonts on different computer monitors. 10

11 With an OS, you just click an icon or a command menu item. 11

12 Early Personal Operating Systems 12

13 Personal Computing in 80 s 13

14 First IBM- PC 14

15 Microsoft DOS 15

16 Apple Macintosh OS 16

17 Modern Operating Systems 17

18 Examples of Modern OS Microsoft Windows (95, 98, XP, Vista, 7, 8) Apple Macintosh Disk Operating Systems (version 1, 2,, 7, 8, 9). Apple OS X (Pather, Tiger, Leopard, Snow Leopard, Lion, Mountain Lion, Maverick) Linux and Android Apple ios (1,2,3,4,5,6,7) 18

19 Windows XP 19

20 Windows 7 20

21 Windows 8 21

22 Apple OS X Tiger (10.4) 22

23 Apple OS X Snow Leopard (10.6) 23

24 Linux OS 24

25 Android OS 25

26 Apple ios 26

27 Today, most Graphical User Interfaces (GUI) look very similar to each other. 27

28 Windows Command Line Interface 28

29 OS X Command Line Interface 29

30 What is inside an OS? 30

31 Layers in a Computer System Hardware Operating System & File System GUI & Applications 31

32 An OS is responsible for presenting an easy- to- use user interface ( look & feel ) keeping track of all user data managing all hardware, e.g., sound, printers, networks, hard disks, display, mouse, keyboard, etc. executing applications starting up or shutting down a computer 32

33 Every OS has its own set of operational features. 33

34 An OS is a very complex piece of software. 34

35 A modern OS may take 1000 programmers over 10 years to design and build. 35

36 Most Important Parts of an OS 1. User Interfaces 2. Application Management 3. File Systems 4. Networking 36

37 Which of the following is different from the rest? a. Windows 7 b. Windows XP c. Linux d. Mac OS X e. Adobe Photoshop 37

38 Which is not a function of an OS? a. printing b. networking c. gaming d. managing user data e. connecting to mouse/keyboard 38

39 What is a File System? 39

40 A File System is an organizer of our secondary storage. 40

41 Every computer has primary storage called Random Access Memory (or RAM). 41

42 RAM Modules (for Personal Computer) 42

43 RAM Modules (for Personal Computer) (for laptop) 43

44 Today, the size of RAM typically ranges from 1GB to 8GB. RAM costs about $10 per GB. 44

45 We need RAM to run applications, the more the better. 45

46 When a computer shuts down, the content of RAM disappears. 46

47 RAM needs electrical power to keep its content. 47

48 RAM is relatively expensive; most computers have limited amount. 48

49 In order to store massive amount of data, we need secondary storage. 49

50 Secondary Storage: a Hard Drive 50

51 A hard disk ranges from 500GB to 2TB, and costs $0.1 per GB. 51

52 Windows Hard Drives 52

53 OS X Hard Drives 53

54 Data stored on a hard drive is permanent; they don t disappear without electrical power. 54

55 RAM is about 100X more expensive than a hard drive; but, it is 1 million times faster! 55

56 A 500GB HD can store 100,000 JPEG images, 150,000 MP3 songs, or 500 hours of digital videos. 56

57 A File System helps us organize our data files, e.g., documents, music, videos, pictures, applications, etc. 57

58 Common File Systems Every computer comes with an OS and a hard drive preinstalled. On Windows, the default file system is called NTFS (New Technology File System) or FAT. On OS X, the default file system is called HFS+ (Hierarchical File System Plus), or Mac OS Extended. 58

59 Formatting a new Hard Drive A new hard drive must be formatted before it can be used. Formatting a hard drive means setting up a new File System by erasing all its data. Today, most new hard drives will be preformatted with either Windows or Apple OS X File Systems. 59

60 Formatting in Windows right click on a drive 60

61 Formatting in OS X OS M. X Cheng, Disk Computer UtilityScience 61

62 Which is not a File System? a. FAT b. NTFS c. HFS+ d. FAT32 e. OS X 62

63 A File System contains Files and Folders (or Directories). 63

64 Files & Folders in Windows Folders Files 64

65 Each file/folder has access permissions, i.e., who owns it, and who is allowed to read, write, execute, or modify. 65

66 Permissions in Windows A Folder A File 66

67 Files & Folders in OS X 67

68 Permissions in OS X A Folder A File 68

69 Window Pathnames Each file/folder has a unique pathname, which is the path from the top to itself. For example, the pathname C:\Users\Mantis\Desktop\Computer Fundamentals is a path for the folder Computer Fundamentals starting from the top C:\ 69

70 Windows Pathnames C:\Users\Mantis\Desktop\Computer Fundamentals 70

71 OS X Pathnames Each file/folder has a unique pathname, which is the path from the top to itself. For example, the pathname Macintosh HD/Users/mcheng/My Work/Teaching/100/spring.2013 is a path for the folder spring.2013 starting from the top Macintosh HD 71

72 OS X Pathnames Macintosh HD/Users/mcheng/My Work/Teaching/100/spring

73 Multitasking 73

74 A modern OS can run several applications at once. 74

75 Time Multiplexing 75

76 Multitasking uses time- multiplexing to run multiple applications at the same time. 76

77 Windows Task Manager 77

78 OS X Activity Monitor 78

79 The End. 79