计算机文化.ppt

Chapter 4,Operating Systems and File Management,Chapter 4:Operating Systems and File Management,2,Chapter Contents,Section A:Operating System BasicsSection B:Todays Operating SystemsSection C:File BasicsSection D:File ManagementSection E:Backup Security,FastPoll True/False QuestionsAnswer A for True and B for False,040100 An operating system manages a computers resources such as the processor,RAM,and storage space.040200 Multithreading provides process and memory management services that allow two or more tasks,jobs,or programs to run simultaneously.040300 GUI stands for“graphic usability icons.”040400 A bootstrap program is a popular type of application software.040500 During a computing session,the operating system is executed from RAM.,Chapter 4:Operating Systems and File Management,3,FastPoll True/False QuestionsAnswer A for True and B for False,040600 The Windows kernel is the same as the Mac OS kernel.040700 Macs featured a graphical user interface before PCs.040800 Boot Camp is a dual boot utility for Macs.040900 Mac files have a data fork and a resource fork.041000 Fedora,Mandrivia,and SUSE are Linux distributions.041100 A disk partition is basically a folder.,Chapter 4:Operating Systems and File Management,4,FastPoll True/False QuestionsAnswer A for True and B for False,041200 A file specification is also called a path.041300 Windows Explorer is a file management utility.041400 Disks are formatted into tracks and sectors.041500 Time Machine is synchronization software used for backup on Macs.041600 To repopulate a new hard disk from an incremental backup,you have to first restore a full backup.041700 A boot disk contains a complete copy of your computers hard disk as it existed when the computer was new.,Chapter 4:Operating Systems and File Management,5,Chapter 4:Operating Systems and File Management,6,Operating System Basics,Operating System ActivitiesUser InterfacesThe Boot Process,Question,042100 A computer handles many tasks simultaneously.Which one of the following refers to the processors ability to handle multiple tasks,rather than the operating systems ability to do so?A.Multi-coreB.MultitaskingC.MultithreadingD.Multiprocessing,Chapter 4:Operating Systems and File Management,7,Chapter 4:Operating Systems and File Management,8,Operating System Activities,An operating system is a type of system software that acts as the master controller for all activities that take place within a computer system,Chapter 4:Operating Systems and File Management,9,Operating System Activities,Chapter 4:Operating Systems and File Management,10,Operating System Activities,Multitasking provides process and memory management services that allow two or more tasks,jobs,or programs to run simultaneouslyWithin a single program,multithreading allows multiple parts,or threads,to run simultaneouslyAn operating systems multiprocessing capability supports a division of labor among all the processing units,Chapter 4:Operating Systems and File Management,11,Operating System Activities,Operating System CategoriesSingle-user operating systemMultiuser operating systemServer operating systemDesktop operating system,Chapter 4:Operating Systems and File Management,12,User Interfaces,The combination of hardware and software that helps people and computers communicate with each other,Chapter 4:Operating Systems and File Management,13,User Interfaces,Menus,submenus,and dialog boxes,Chapter 4:Operating Systems and File Management,14,The Boot Process,During the boot process,the operating system kernel is loaded into RAMThe kernel provides essential operating system servicesYour computers small bootstrap program is built into special ROM circuitry housed in the computers system unit,The Boot Process,Chapter 4:Operating Systems and File Management,15,Chapter 4:Operating Systems and File Management,16,Todays Operating Systems,Microsoft WindowsMac OSUNIX and LinuxDOSHandheld Operating Systems,Question,042200 Todays popular operating systems include Windows,Mac OS,Linux,Android,and Google Chrome.Each has strengths and weaknesses that are important to understand.Which of the following statements is correct?A.Google Chrome is built on the Windows kernel,so it is ideal for netbooks because it has good resistance to malware.B.If you dont like the user interface for Windows but want to run the vast variety of Windows software,you can install Linux.C.Linux and Mac OS have a reputation for being more stable than Windows.D.Windows includes software called Boot Camp that allows PCs to boot into different operating systems,such as Mac OS,Linux,Chrome,and Android.,Chapter 4:Operating Systems and File Management,17,Microsoft Windows,Chapter 4:Operating Systems and File Management,18,Chapter 4:Operating Systems and File Management,19,Mac OS,You can tell when youre using Mac OS by the Apple logo that appears on the menu bar.TheMac OS X interface includes all the standard elements of a GUI,including icons,menus,windows,and taskbars.,Chapter 4:Operating Systems and File Management,20,Mac OS,On a Macintosh computer with Boot Camp,you can boot into Mac OS X or into Windows.,Chapter 4:Operating Systems and File Management,21,Mac OS,Mac OS X on an Intel Mac offers the ability to run Windows and Windows application software in addition to software designed for the MacintoshDual bootVirtual machine,Chapter 4:Operating Systems and File Management,22,UNIX and Linux,The UNIX operating system was developed in 1969 at AT&Ts Bell LabsDependable in multiuser environmentsLinux is an operating system distributed along with its source code under the terms of a GPL(General Public License)A Linux distribution is a download that contains the Linux kernel,system utilities,applications,and an installation routine,Chapter 4:Operating Systems and File Management,23,UNIX and Linux,Linux users can choose from several graphical interfaces.Pictured here is the popular Ubuntu graphical desktop.,Chapter 4:Operating Systems and File Management,24,DOS,Disk Operating SystemFirst operating system that many used,Chapter 4:Operating Systems and File Management,25,Handheld Operating Systems,Chapter 4:Operating Systems and File Management,26,File Basics,File Names and ExtensionsFile Directories and FoldersFile Formats,Question,042300 Suppose a friend sends you a file called Twain.dll.From the file name,what can you deduce?A.That it is a word processing document,probably about Mark Twain.B.That you should be able to open it using Microsoft Word.C.That the file extension makes it a virus.D.That it is a support program file,perhaps part of the device driver for your scanner.,Chapter 4:Operating Systems and File Management,27,Chapter 4:Operating Systems and File Management,28,File Names and Extensions,You must adhere to file-naming conventions when saving filesMaximum lengthProhibited charactersNo reserved wordsCase sensitivityFile extensions are usually related to the file formatNative file format,File Directories and Folders,To designate a files location,you must first specify the device where the file is storedThe main hard disk usually is referred to as Drive CA disk partition is a section of hard disk drive that is treated as a separate storage unitPartitions can be assigned drive lettersPartitions are not the same as folders,Chapter 4:Operating Systems and File Management,29,Chapter 4:Operating Systems and File Management,30,File Directories and Folders,An operating system maintains a directory for each disk,tape,CD,DVD,BD,or USB flash driveRoot directorySubdirectoryDepicted as foldersA computers file location is defined by a file specification,or path,Chapter 4:Operating Systems and File Management,31,File Formats,A file format refers to the organization and layout of data that is stored in a fileThe format of a file usually includes a header,data,and possibly an end-of-file markerA file header is a section of data at the beginning of a file that contains information about a fileA file extension does not really define the format of a file,Chapter 4:Operating Systems and File Management,32,File Formats,A software application can open files that exist in its native file format,plus several additional file formats,Chapter 4:Operating Systems and File Management,33,File Formats,An easy way to convert a file from one format to another is to open it with an application that supports both file formats,and then use the Save As dialogbox to select an alternative file format.,Chapter 4:Operating Systems and File Management,34,File Management,Application-based File ManagementFile Management UtilitiesFile Management MetaphorsWindows ExplorerFile Management TipsPhysical File Storage,Question,042400 Before donating your computer to a charitable organization,you can make sure your personal data cannot be accessed from the hard disk by:A.Deleting any files that contain personal data.B.Deleting files containing personal data and then emptying the Recycle Bin or Trash.C.Deleting all the files and folders on your computers hard disk.D.Deleting all files and folders and then using file shredder software.,Chapter 4:Operating Systems and File Management,35,Chapter 4:Operating Systems and File Management,36,Application-based File Management,Applications typically provide a way to open files and save them in a specific folder on a storage device,Chapter 4:Operating Systems and File Management,37,Application-based File Management,The Save As command of most Windows applications uses the operating systems filemanagement utility,so you can carry out a widevariety of file and folder tasks such as creating,renaming,and deleting files.,Chapter 4:Operating Systems and File Management,38,File Management Utilities,File management utilities show you the files stored on your disks and help you work with them,Chapter 4:Operating Systems and File Management,39,File Management Metaphors,Storage metaphors help you visualize and mentally organize the files on your disksLogical storage models,Chapter 4:Operating Systems and File Management,40,Windows Explorer,Windows Explorer makes it easy to drill down through the levels of the directory hierarchy to locate a folder or file.,Chapter 4:Operating Systems and File Management,41,Windows Explorer,Windows Explorer allows you to manipulate files and folders in the following ways:RenameCopyMoveDelete,Chapter 4:Operating Systems and File Management,42,File Management Tips,Use descriptive namesMaintain file extensionsGroup similar filesOrganize your folders from the top downConsider using the default foldersDo not mix data files and program files,Chapter 4:Operating Systems and File Management,43,File Management Tips,Dont store files in the root directoryAccess files from the hard diskFollow copyright rulesDelete or archive files you no longer needBe aware of storage locationsBack up,Chapter 4:Operating Systems and File Management,44,Physical File Storage,The physical storage model describes what happens on the disks and in the circuits Storage media must be formatted before it can store filesFormatting utilities divide the disk into tracks and sectors,Chapter 4:Operating Systems and File Management,45,Physical File Storage,CDs and DVDs can be created using mastering or packet-writing techniques.Mastering creates discs that can be used more reliably on a wide varietyof computers and standalone players.Packet writing is more flexible for disks that you plan to use only on your own computer.,Chapter 4:Operating Systems and File Management,46,Physical File Storage,The file system keeps track of the names and locations of filesNTFSMaster File Table(MFT)FAT32File Allocation Table(FAT),Chapter 4:Operating Systems and File Management,47,Physical File Storage,Deleting a file changes the status of that files clusters to empty and removes the file name from the index fileThe files data is still thereFile shredder software overwrites“empty”sectors with random 1s and 0sFiles in the Windows Recycle Bin and similar utilities can be undeleted,Chapter 4:Operating Systems and File Management,48,Physical File Storage,Fragmented files are stored in noncontiguous clusters and decrease performanceDefragmentation utilities rearrange files so that they are stored in contiguous clusters,Chapter 4:Operating Systems and File Management,49,Backup Security,Backup BasicsFile Copies and SynchronizationSystem SynchronizationFile and System BackupBare-metal Restore and Virtual Machines,Question,042500 Copying important data files from your computers hard disk to an optical disk or flash drive is a simple way to back up data.It is not a total backup solution,however.Why not?A.You cannot restore these files to a new hard disk without the activation codes.B.The backup is bootable,but it wont start your computer if the hard disk fails.C.You have not backed up your programs or your personal settings.D.You have not backed up the restore points needed to reconfigure the Windows Registry for a new hard disk.,Chapter 4:Operating Systems and File Management,50,Chapter 4:Operating Systems and File Management,51,Backup Basics,A backup stores the files needed to recover data thats been wiped out by operator error,viruses,or hardware failures,Chapter 4:Operating Systems and File Management,52,Backup Basics,Your backup schedule depends on how much data you can afford to loseYou should run an up-to-date virus check as the first step in your backup routineThe backup device you select depends on the value of your data,your current equipment,and your budget,Backup Basics,Chapter 4:Operating Systems and File Management,53,Chapter 4:Operating Systems and File Management,54,File Copies and Synchronization,Unique files are difficult to reproduceManually copying and pasting requires you to select the files and destination device each timeFile synchronization software ensures that files in two or more locations contain the same dataOriginated with PDATo restore from a data file backup,you simply copy files from your backup to your hard disk,File Copies and Synchronization,Chapter 4:Operating Systems and File Management,55,Chapter 4:Operating Systems and File Management,56,System Synchronization,Backs up all files and system software on your computerTime MachineThe number of backups depends on the capacity of your backup drive,and the frequency at which you make changes,File and System Backup,Chapter 4:Operating Systems and File Management,57,Chapter 4:Operating Systems and File Management,58,File and System Backup,A full backup makes a fresh copy of every file in the folders youve specified for the backupA differential backup makes a backup of only those files that were added or changed since your last full backup sessionAn incremental backup makes a backup of the files that were added or changed since the last backupnot necessarily the files that changed from the last full backupMost experts recommend that you keep more than one set of backups,System Backup,Chapter 4:Operating Systems and File Management,59,Chapter 4:Operating Systems and File Manag