CHAPTER Four ： File Management, Virus Protection and Backup 第 4 章：文件管理、病毒防护和备份.

CHAPTER Four ： File Management, Virus Protection and Backup 第 4 章：文件管理、病毒防护和备份

of 109 Table Of Contents File Basics 4.14.1 File Management 4.24.2 Computer Viruses 4.34.3 4.44.4 Data Backup

of 109 4.1.1 Filenames, Extensions, and FormatsFilenames, Extensions, and Formats 4.1.2 File Locations, Folders and PathsFile Locations, Folders and Paths 4.1.3 File Sizes and DatesFile Sizes and Dates File Basics

of 109 4.1.1 Filenames, Extensions, and Formats What is a computer file?  A computer file ( 计算机文件 ), or simply "a file", is defined as a named collection of data that exists on a storage medium, such as a hard disk, floppy disk, CD, DVD, or tape. Computer files have several characteristics, such as a name, format, location, size, and date. File Basics

of 109 What are the rules for naming files?  Every file has a name and might also have a filename extension.  When you save a file, you must provide it with a valid filename that adheres to specific rules, referred to as file-naming conventions ( 文件命名规则 ).  Each operating system has a unique set of file-naming conventions. File Basics

of 109 Why are certain characters and words not allowed in a filename?  If an operating system attaches special significance to a symbol, you might not be able to use it in a filename.  Some operating systems also contain a list of reserved words ( 保留字 ) that are used as commands or special identifiers. You cannot use these words alone as a filename. File Basics

of 109 File Basics Are filename extensions important?  A filename extension ( 文件名的扩展名 ), or "file extension", is an optional file identifier that is separated from the main filename by a period, as in Paint.exe.  If a file has the right extension for a particular application program, you'll see it in the list of files that you can open with that software. For example, files with a.doc extension appear in the Open and Save As lists when you're working with Microsoft Word software.

of 109 File Basics  A filename extension is usually related to the file format ( 文件格式 ), which is defined as the arrangement of data in a file and the coding scheme that is used to represent the data.  Most software programs have what’s called a native file format ( 专用文件格式 ) that is used to store files. For example, Microsoft Word stores files in DOC format, whereas Adobe Illustrator stores graphics files in Al format.

of 109 4.1.2 File Locations, Folders, and Paths How do I designate a file's location?  To designate a file's location, you must first specify where the file is stored.  Each of a PC's storage devices is identified by a device letter — a convention that is specific to DOS and Windows. File Basics

of 109 File Basics  The floppy disk drive is usually assigned device letter A and is referred to as "drive A". A device letter is usually followed by a colon, so drive A could be designated as A: or as 3 1 / 2 " Floppy (A:).  The main hard disk drive is usually referred to as "drive C".  Additional storage devices can be assigned letters from D through Z.

of 109 File Basics What's the purpose of folders?  An operating system maintains a list of files called a directory ( 目录 ) for each storage disk, tape, CD, or DVD.  The main directory of a disk is referred to as the root directory ( 根目录 ).  On a PC, the root directory is typically identified by the device letter followed by a backslash (\). For example, the root directory of the hard disk drive would be C:\.

of 109 File Basics  A root directory can be subdivided into smaller lists, called subdirectories ( 子目录 ). When you use Windows, Mac OS, or a Linux graphical file manager, these subdirectories are depicted as folders ( 文件夹 ). Each folder has a name. Folders can be created within other folders.  A folder name is separated from a drive letter and other folder names by a special symbol. In DOS and Windows, this symbol is the backslash (\).

of 109 File Basics  By storing a file in a folder, you assign it a place in an organized hierarchy of folders and files.  A computer file’s location is defined by a file specification ( 文件说明 ), sometimes called a path ( 路径 ), which includes the drive letter, folder(s), filename, and extension.

of 109 File Basics 4.1.3 File Sizes and Dates What's the significance of a file's size?  A file contains data, stored as a group of bits. The more bits, the larger the file. File size ( 文件大小 ) is usually measured in bytes, kilobytes, or megabytes.  Your computer's operating system keeps track of file sizes and provides that information to you when you request a listing of files.

of 109 File Basics Is the file date important?  Your computer keeps track of the date that a file was created or last modified.  The file date ( 文件日期 ) is useful if you have created several versions of a file and want to make sure that you know which version is the most recent. It can also come in handy if you have downloaded several updates of a software package and you want to make sure that you install the latest version.

File Basics

of 109 File Management 4.2.1 Application-based File ManagementApplication-based File Management 4.2.2 File Management UtilitiesFile Management Utilities 4.2.3 File Management MetaphorsFile Management Metaphors 4.2.4 Windows ExplorerWindows Explorer 4.2.5 Physical File StoragePhysical File Storage

of 109 File Management What's the file management?  File management ( 文件管理 ) encompasses any procedure that helps you organize your computer-based files so that you can find and use them more efficiently.  Depending on your computer's operating system, you may be able to organize and manipulate your files from within an application program, or by using a special file management utility provided by the operating system.

of 109 File Management 4.2.1 Application-based File Management How does a software application help me manage files?  Applications typically provide a way to open files and save them in a specific folder on a designated storage device.  An application might also provide additional file management capabilities, such as deleting and renaming files.

File Management

of 109 File Management What's the difference between the Save option and the Save As option?  The Save As option allows you to select a name and storage device for a file, whereas the Save option simply saves the latest version of a file under its current name and at its current location.  When you try to use the Save option for a file that doesn’t yet have a name, your application will display the Save As dialog box.

File Management

of 109 File Management What other options does the Save As dialog box provide?  The Save As dialog box that is displayed by Windows applications not only helps you select a name and destination drive for a file, it also allows you to rename files, delete files, create folders, and rename them.

File Management

of 109 File Management 4.2.2 File Management Utilities How does the operating system help me manage files?  Most operating systems provide file management utilities ( 文件管理实用工具 ) that give you the "big picture" of the files you have stored on your disks and help you work with them. These utilities help you view a list of files, find files, move files from one place to another, make copies of files, delete files, discover file properties, and rename files.

of 109 File Management 4.2.3 File Management Metaphors How does a metaphor help me visualize the "big picture" for my file storage?  File management utilities often use some sort of storage metaphor ( 存储摸式 ) to help you visualize and mentally organize the files on your disks and other storage devices. These metaphors are also called logical storage models ( 逻辑存储模式 ).

of 109 File Management What storage metaphors are typically used for personal computers?  After hearing so much about files and folders, you might have guessed that the filing cabinet is a popular metaphor for computer storage.  In this metaphor, each storage device of a computer corresponds to one of the drawers in a filing cabinet. The drawers hold folders and the folders hold files.

of 109 File Management  Another storage metaphor is based on a hierarchical diagram that is sometimes referred to as a "tree structure".  In this metaphor, a tree represents a storage device. The trunk of the tree corresponds to the root directory. The branches of the tree represent folders. These branches can split into small branches representing folders within folders. The leaves at the end of a branch represent the files in a particular folder.

File Management

of 109 File Management 4.2.4 Windows Explorer How do I use a file management utility?  As an example of a file management utility, let's take a closer look at Windows Explorer (Windows 资源管理器 ), a utility program that is bundled with the Windows operating system, and is designed to help you organize and manipulate the files stored on your computer.

of 109 File Management  The Windows Explorer window is divided into two "window panes". The pane on the left side of the window lists each of the storage devices connected to your computer, plus several important system objects, such as My Computer, Network Neighborhood, and the Desktop.  Once a device icon or folder is opened, its contents appear in the pane on the right side of the Windows Explorer window.

File Management

of 109 File Management What can I do with the folders and files that are listed in Windows Explorer?  In addition to locating files and folders, Windows Explorer provides a set of tools that will help you manipulate files and folders in the following ways: Rename 重命名 Copy 复制 Move 移动 Delete 删除

File Management

of 109 File Management How can I work with more than one file at a time?  To work with a group of files or folders, you must first select them.  You can accomplish this task in several ways. You can hold down the Ctrl key as you click each item. As an alternative, you can hold down the Shift key while you click the first item and the last item that you want to select.

of 109 File Management 4.2.5 Physical File Storage Is data stored in specific places on a disk?  The structure of files and folders that you see in Windows Explorer is what's called a "logical" model—logical because it is supposed to help you create a mental picture.  The physical storage model ( 物理存储模式 ) describes what actually happens on the disks and in the circuits.

of 109 File Management  Before a computer can store a file on a disk, CD, or DVD, the storage medium must be formatted.  The formatting ( 格式化 ) process creates the equivalent of electronic storage bins by dividing a disk into tracks ( 磁道 ), and then further dividing each track into sectors ( 扇区 ). Tracks and sectors are numbered to provide addresses for each data storage bin.

File Management 软盘和硬盘上的磁道是同心圆排列的。 CD 和 DVD 上的磁道是从光盘中心螺旋形的向外排列。

of 109 File Management 补充：磁盘容量是如何计算得到的 ? - 磁盘中可记录信息的磁介质表面叫做记录面。一个硬盘驱动器可装有多个盘片，每个盘片可以提供两个记录面（盘片的正反两面），每个记录面都配有一个独立的读写磁头。 - 每个记录面上都分布着若干条同心的圆环，称为磁道，数据就记录在磁道上。使用时要对磁道进行编号，按照半径递减的顺序从外到里编号，最外一圈为 0 道，向内的磁道号依次增加。

of 109 File Management 补充：磁盘容量是如何计算得到的 ? （续） - 为了便于记录信息，每条磁道又分成若干段，每一段称为一个扇区。 - 为了简化电路设计，规定每个磁道上记录的比特数目是相同的，因此不同磁道上的位密度（指在磁道圆周上单位长度内存储的二进制位数）是不一样的。 - 格式化后的磁盘容量的计算公式为：磁盘容量 = 每个扇区的字节数 × 每道的扇区数 × 每个记录面的磁道数 × 记录面数

of 109 File Management How does a disk get formatted?  Today, most storage devices are preformatted at the factory; however, computer operating systems provide formatting utilities ( 格式化实用工具 ) that you can use to reformat some storage devices — typically hard disks.  When you use a formatting utility, it erases any data that happens to be on the disk, then prepares the tracks and sectors necessary to hold data.

of 109 File Management How does the operating system keep track of a file's location?  The operating system uses a file system ( 文件系统 ) to keep track of the names and locations of files that reside on a storage medium, such as a hard disk.  Different operating systems use different file systems. Linux: Ext2fs (Extended 2 file system) Mac OS: HFS (Hierarchical File System) Windows NT/2000/XP: NTFS (New Technology File System)

of 109 File Management  To speed up the process of storing and retrieving data, a disk drive usually works with a group of sectors called a cluster ( 簇 ) or a "block".  A file system's primary task is to maintain a list of clusters and keep track of which are empty and which hold data. This information is stored in a special file.  If your computer uses the FAT32 file system, for example, this special file is called the File Allocation Table (FAT, 文件分配表 ).

of 109 File Management  When you save a file, your PC's operating system looks at the FAT to see which clusters are empty. It will select one of these clusters, record the file data there, and then revise the FAT to include the filename and its location.  A file that doesn't fit into a single cluster spills over into the next contiguous cluster unless that cluster already contains data.  When you want to retrieve a file, the OS looks through the FAT for the filename and its location.

File Management

of 109 File Management What happens when a file is deleted?  When a file is deleted, the operating system simply changes the status of the file's clusters to "empty" and removes the filename from the FAT. The filename no longer appears in a directory listing, but the file's data remains in the clusters until a new file is stored there.  To delete data from a disk in such a way that no one can ever read it, you can use special file shredder software ( 文件粉碎软件 ) that overwrites "empty" sectors with random 1s and 0s.

of 109 How does the Recycle Bin affect file deletions?  Instead of marking a file's FAT clusters as available, the operating system moves the file to the Recycle Bin folder.  The "deleted" file still takes up space on the disk, but does not appear in the usual directory listing. The file does, however, appear in the directory listing for the Recycle Bin folder, and you can undelete any files in this listing. File Management

of 109 How does a disk become fragmented?  As a computer writes files on a disk, parts of files tend to become scattered all over the disk.  These fragmented files ( 成为碎片的文件 ) are stored in noncontiguous clusters.  To regain peak performance, you can use a defragmentation utility ( 碎片整理实用工具 ) to rearrange the files on a disk so that they are stored in contiguous clusters. File Management

of 109 Lab6: 使用 Excel 2003 （实验要求：在英文版 WindowsXP 环境下完成实验内容） Labs

of 109 lab6-Excel2003 的使用 lab6-Excel2003 的使用 lab6-Excel2003 使用实验指导 lab6-Excel2003 使用实验指导 Execel2003 电子表格软件实验用文件 Execel2003 电子表格软件实验用文件 Labs 相关资源

of 109 Computer Viruses 4.3.1 Viruses, Trojan Horses and WormsViruses, Trojan Horses and Worms 4.3.2 Antivirus softwareAntivirus software 4.3.3 Virus HoaxesVirus Hoaxes

of 109 Computer Viruses 4.3.1 Viruses, Trojan Horses and Worms What's the technical definition of a virus?  A computer virus ( 计算机病毒 ) is a set of program instructions that attaches itself to a file, reproduces itself, and spreads to other files.  Viruses can corrupt files, destroy data, display an irritating message, or otherwise disrupt computer operations.

of 109 Computer Viruses  A common misconception is that viruses spread themselves from one computer to another. They can only replicate themselves on the host computer.  A key characteristic of viruses is their ability to "lurk" in a computer for days or months, quietly replicating themselves.  Viruses spread because people distribute infected files by exchanging disks and CDs, sending e-mail attachments, and downloading software from the Web.

of 109 Computer Viruses  A computer virus generally infects the files executed by your computer. When your computer executes an infected program, it also executes the attached virus instructions. These instructions then remain in RAM, waiting to infect the next program that your computer runs, or the next disk that it accesses.  In addition to replicating itself, a virus might perform a trigger event ( 触发事件 ).

of 109 Computer Viruses  Viruses can be classified by the types of files they infect. A virus that attaches to an application program is known as a file virus ( 文件病毒 ). A boot sector virus ( 引导扇区病毒 ) infects the system files that your computer uses every time you turn it on. A macro virus ( 宏病毒 ) infects a set of instructions called a "macro". A macro( 宏 ) is essentially a miniature program that usually contains legitimate instructions.

of 109 Computer Viruses How is a Trojan horse different from a virus?  A Trojan horse ( 特洛伊木马 ) is a computer program that seems to perform one function while actually doing something else.  Technically, it is not the same as a virus because, unlike a virus, a Trojan horse is not designed to make copies of itself. Trojan horses are notorious for stealing passwords. Some Trojan horses delete files and cause other trouble.

of 109 Computer Viruses  特洛伊木马没有复制能力，它的特点是伪装成一个实用工具或者一个可爱的游戏，这会诱使用户将其安装在 PC 或者服务器上。  “ 特洛伊木马 ” 这个名称来源于希腊神话 “ 木马屠城记 ” ：希腊联军围困特洛伊久攻不下，于是假装撤退，留下一具巨大的中空木马，特洛伊守军不知是计，把木马运进城中作为战利品。夜深人静之际，木马腹中躲藏的希腊士兵打开城门，特洛伊沦陷。后人常用 “ 特洛伊木马 ” 这一典故，用来比喻在敌方营垒里埋下伏兵里应外合的活动。如今黑客程序借用其名，有 “ 一经潜入，后患无穷 ” 之意。

of 109 Computer Viruses  完整的木马程序一般由两个部分组成：一个是服务器端，一个是客户端。 “ 中了木马 ” 就是指安装了木马的客户端程序，若你的电脑被安装了客户端程序，则拥有相应服务器端的人就可以通过网络控制你的电脑、为所欲为，这时电脑上的各种文件、程序以及在你电脑上使用的账号、密码无安全可言了。  木马程序不能算是一种病毒，但可以和最新病毒、漏洞利用工具一起使用用，几乎可以躲过各大杀毒软件，所以不要认为使用有名的杀毒软件电脑就绝对安全，木马永远是防不胜防的，除非你不上网。

of 109 Computer Viruses What's a worm?  Unlike a virus, which is designed to spread from file to file, a worm ( 蠕虫 ) is designed to spread from computer to computer.  Most worms take advantage of communications networks — especially the Internet — to travel within e-mail and TCP/IP packets, jumping from one computer to another.

of 109 Computer Viruses How are viruses spread?  Viruses can slip into your computer from a variety of sources. Be cautious of floppy disks, homemade CDs, and Web sites that contain games and other supposedly fun stuff. They are a common source of file viruses, boot sector viruses, and Trojan horses.  E-mail attachments are another common source of viruses.  Macro viruses tend to hang out in documents and spreadsheets.

Computer Viruses

of 109 Computer Viruses What are the symptoms of a virus?  The symptoms depend on the virus. The following symptoms might indicate that your computer has contracted a virus: Your computer displays vulgar, embarrassing, or annoying messages. Your computer develops unusual visual or sound effects. You have difficulty saving files, or files mysteriously disappear. Your computer suddenly seems to work very slowly.

of 109 Computer Viruses Your computer reboots unexpectedly. Your executable files unaccountably increase in size. Your computer starts sending out lots of e-mail messages on its own.  However, some viruses, worms, and Trojan horses have no recognizable symptoms. To avoid being a pawn in some hacker's destructive plot, you should use antivirus software to evict any viruses, worms, or Trojan horses that try to take up residence in your computer.

of 109 Computer Viruses 4.3.2 Antivirus software What should I do if my computer gets a virus?  Antivirus software ( 防病毒软件 ) is a set of utility programs that looks for and eradicates viruses, Trojan horses, and worms. This essential software is available for handheld computers, personal computers, and servers.

of 109 How does antivirus software work?  The earliest antivirus software simply examined the programs on a computer and recorded their length. A change in the length of a program from one computing session to the next indicated the possible presence of a virus.  This method of virus detection requires that you start with a virus-free copy of the program. Computer Viruses

of 109 Computer Viruses  Later, antivirus software is designed to examine the bytes in an uninfected application program and calculate a checksum. A checksum ( 校验和 ) is a number that is calculated by combining the binary values of all bytes in a file.  Each time you run an application program, the antivirus software calculates the checksum and compares it with the previous checksum. If any byte has changed, the checksum will be different, and the antivirus software assumes that a virus is present.

of 109 Computer Viruses  Most of today's antivirus software can identify viruses, Trojan horses, and worms by searching files for virus signatures.  A virus signature ( 病毒签名 ) is usually a section of the virus program, such as a unique series of instructions, that can be used to identify a known virus, much as a fingerprint is used to identify an individual.  The signature search technique is fairly quick, but it identifies only those viruses with a known signature. To detect new viruses virus detection software must be updated regularly.

of 109 Computer Viruses When should I use antivirus software?  The short answer is "all the time". Most antivirus software allows you to specify what to check and when to check it.  The best practice, however, is to keep your antivirus software running full-time in the background so that it scans all files the moment they are accessed, and checks every e-mail message as it arrives.

of 109 Computer Viruses How often should I get an update?  The information that your antivirus software uses to identify and eradicate viruses, Trojan horses, and worms is stored in one or more files usually referred to as "virus definitions".  To keep up with these newly identified pests, antivirus software publishers provide virus definition updates, which are usually available as Web downloads.

of 109 Computer Viruses  You should check your antivirus publisher's Web site for the latest updates of antivirus software every few days.  Some antivirus vendors feature an electronic update service that periodically reminds you to check for updates. When you provide the go-ahead, your computer connects to your antivirus vendor's Web site, downloads updated virus definitions and installs them.

of 109 Computer Viruses How reliable is antivirus software?  Considering the sheer number of viruses that exists and the number of new viruses that debuts every week, antivirus software is surprisingly reliable at identifying and eradicating viruses, Trojan horses, and worms.  Viruses try to escape detection in many ways. Unfortunately, antivirus software is not 100% reliable.

of 109 Computer Viruses Multi-partite viruses ( 多分裂病毒 ) are able to infect multiple types of targets. Polymorphic viruses ( 多态病毒 ) mutate to escape detection by changing their signatures. Stealth viruses ( 秘密行动病毒 ) remove their signatures from a disk-based file and temporarily conceal themselves in memory. Some viruses—called retro viruses ( 火箭病毒 )—are designed to attack antivirus software by deleting the files that contain virus descriptions, or corrupting the main executable virus program.

of 109 Computer Viruses 4.3.3 Virus Hoaxes What's a virus hoax?  A virus hoax ( 病毒恶作剧 ) usually arrives as an e-mail message containing dire warnings about a supposedly new virus that is on the loose.  The message typically suggests some strategy for avoiding the virus, and recommends that you forward the e-mail warning to all of your friends and colleagues.

of 109 Computer Viruses How do I recognize a hoax?  Bogus virus e-mail messages usually contain a long list of people in the To: and Cc: boxes. They have been forwarded many times. Some "authority" is usually cited to make you think that the alert is official.  Most hoaxes include a recommended procedure for eradicating the virus. Fake viruses are often characterized as doing bizarre deeds.

of 109 Computer Viruses Are any virus e-mail warnings real?  You might receive several types of legitimate virus warnings.  A person experienced in dealing with viruses might also send you the Web links to an antivirus site where you could find more information about the virus.

of 109 Computer Viruses What should I do about virus hoaxes?  When you receive an e-mail message about a virus, don't panic. Virtually all of them are hoaxes. If you are uncertain, check one of the many antivirus Web sites. There you can look up the alleged virus by name to see if it is a hoax or a real threat.  Under no circumstances should you forward virus hoax messages to other people.

of 109 Data Backup 4.4.1 Backup and Restore ProcedureBackup and Restore Procedure 4.4.2 Backup EquipmentBackup Equipment 4.4.3 Backup SoftwareBackup Software

of 109 Data Backup 4.4.1 Backup and Restore Procedure How do I make a backup?  A backup ( 备份 ) is a copy of one or more files that has been made in case the original files become damaged. A backup is usually stored on a different storage medium from the original files.  The exact steps that you follow to make a backup depend on your backup equipment, the software you use to make backups, and your personal backup plan.

Data Backup

of 109 Data Backup How do I restore data?  In technical jargon, you restore data by copying files from a backup to the original storage medium or its replacement.  As with the procedures for backing up data, the process that you use to restore data to your hard disk varies, depending on your backup equipment and software.  Most software designed to back up and restore data allows you to select which files you want to restore.

of 109 Data Backup What's the best backup plan?  A good backup plan allows you to restore your computing environment to its pre- disaster state with a minimum of fuss.  Unfortunately, no single backup plan fits everyone's computing style or budget. You must devise your own backup plan that's tailored to your particular computing needs.

Data Backup

of 109 Data Backup Do I have to back up every file?  A full-system backup ( 完整的系统备份 ) contains a copy of every program, data, and system file on a computer.  The advantage of a full system backup is that you can easily restore everything to its pre-disaster state simply by copying the backup files to a new hard disk.  A full-system backup takes a lot of time, however, and fully automating the process requires a large-capacity storage device.

of 109 Data Backup  A pretty good alternative to a full system backup is a "selective" backup that contains only your most important data files. The backup process can be simplified if you've stored all of your important data files in one folder or its subfolders.  The disadvantage of this backup strategy is that because you backed up only data files, you must manually reinstall all of your software, in addition to restoring your data files.

of 109 Data Backup  In addition to data files that you create, a few other types of data files might be important to you. Consider making backups of the following files: Internet connection information E-mail folders E-mail address book Favorite URLs Downloads

of 109 Data Backup What about the Windows Registry?  The Registry is an important group of files used by the Windows operating system to store configuration information about all of the devices and software installed on a computer system.  If the Registry becomes damaged, your computer might not be able to boot up, launch programs, or communicate with peripheral devices. It is a good idea to have an extra copy of the Registry in case the original file is damaged.

of 109 Data Backup How do I avoid backing up files that contain viruses?  If your antivirus software is not set to constantly scan for viruses on your computer system, you should run an up-to-date virus check as the first step in your backup routine.

of 109 Data Backup How often should I back up my data?  Your backup schedule depends on how much data you can afford to lose. How many sets of backups do I need?  One backup is good, but in case your backup gets corrupted, you should maintain a rotating set of backups.

of 109 Data Backup Will all of my backups contain the same files?  A full backup ( 完全备份 ) makes a fresh copy of every file that exists in the folders that you've specified for the backup.  It is not necessary to make a full backup on every backup date, especially if most of your files don't change from one backup session to another. Instead of making a full backup every time, you can make differential or incremental backups.

of 109 Data Backup  A differential backup ( 差异备份 ) makes a backup of only those files that were added or changed since your last full backup session.  After making a full backup of your important files, you will make differential backups at regular intervals.  If you need to restore all of your files after a hard disk crash, first restore the files from your full backup, then restore the files from your latest differential backup.

of 109 Data Backup  An incremental backup ( 增量备份 ) makes a backup of the files that were added or changed since the last backup— not necessarily the files that changed from the last full backup, but the files that changed since any full or incremental backup.  To restore files from an incremental backup, first files from a full backup are restored, followed by files from each incremental backup, starting with the oldest and ending with the most recent.

of 109 Data Backup How can I be sure that my backups will work?  You should enable the "read after write" or "compare" option provided by backup software. These options force the software to check the data in each sector as it is written to make sure that it is copied without error.  You should also test your backup by trying to restore one file. Try it with one of your least important data files, just in case your backup is faulty.

of 109 Data Backup Do I need a boot disk?  A boot disk ( 引导盘 ), sometimes called an "emergency boot disk, is a floppy disk or CD that contains the operating system files needed to boot your computer without accessing the hard disk.  Several types of boot disks exist, including recovery CDs, Windows Startup Disks, and rescue disks. It is a good idea to have one of each.

of 109 Data Backup A recovery CD ( 恢复光盘 ) contains the operating system files needed to boot the computer, plus all of the Windows and application software files needed to restore your computer to the state it was in when you bought it. A Windows Startup Disk (Windows 启动盘 ) loads not only the operating system, but also the CD-ROM drivers necessary for your computer to access files on the CD-ROM.

of 109 Data Backup A rescue disk ( 救援盘 ) contains operating system files, plus a special version of the antivirus software that can perform the first wave of virus cleanup in RAM and on the hard disk. Where should I store my backups?  Backups should be stored in a safe place, away from the computer.

of 109 Data Backup Can I store my backups on the Internet?  Several Web sites offer fee-based backup storage space. When needed, you can simply download backup files from the Web site to your hard disk. Can I store my files on a network server?  If your computer is connected to a local area network, you might be able to use the network server as a backup device.

of 109 Data Backup 4.4.2 Backup Equipment Is a tape drive the best backup device?  Even with the proliferation of writable CDs and DVDs, tape drives remain the best backup device for personal computers.  Tape is a fairly reliable storage medium, but not as durable as writable CDs and DVDs.

of 109 Data Backup What about writable CDs and DVDs?  Writable optical technologies provide good storage capacity, and blank disks are fairly inexpensive. You can typically use them to back up all of your data files. It might also be feasible to back up your entire system on a series of CDs or DVDs.  The major disadvantage of writable CDs and DVDs is that the writing process is slow — slower than writing data to tape or a removable hard disk.

of 109 Data Backup How about a second hard disk drive?  A second hard disk drive is a good backup option — especially if it has equivalent capacity to your main hard disk.  Unfortunately, your backup hard disk is susceptible to head crashes, making it one of the least reliable storage options. How do I choose a backup device?  The backup device that you select depends on the value of your data, your current equipment, and your budget.

of 109 Data Backup 4.4.3 Backup Software Do I need special software to make a backup?  The software that you use to create your backups depends on your backup plan.  If you are simply copying one or more data files to a flash disk, you can use the Copy command that is provided by your operating system or a file management utility, such as Windows Explorer.

of 109  For complex backup operations, you should use backup software.  Backup software ( 备份软件 ) is a set of utility programs designed to back up and restore files.  It usually provides options that make it easy to schedule periodic backups, define a set of files that you want to regularly back up, and automate the restoration process for incremental and differential backups. Data Backup

of 109 Data Backup Where can I get "real" backup software?  Your operating system is likely to include backup software.  Backup software is supplied with many backup devices, particularly tape drives.  You can also download and purchase backup software from companies that specialize in data protection software.

of 109 Lab7: 使用 PowerPoint 2003 （实验要求：在英文版 WindowsXP 环境下完成实验内容） Labs

of 109 lab7-PowerPoint2003 演示文稿制作 lab7-PowerPoint2003 演示文稿制作 lab7-PowerPoint2003 使用实验指导 lab7-PowerPoint2003 使用实验指导 PowerPoint2003 演示文稿实验用文件 PowerPoint2003 演示文稿实验用文件 Labs 相关资源

of 109 Chapter 4 专业词汇表 KEY TERMS

of 109 Homework 1. 完成教材 P203~204 SUMMARY 中的填空。（ Section D 的填空可以不写） 2. 完成教材 P205~206 SITUATION QUESTIONS 中的填空。 3. 将 SUMMARY （ Section D 部分可以不翻译）和 SITUATION QUESTIONS 的内容翻译成中文，并写在作业本上。 4. 在作业本上写出 Chap4 专业词汇表中的 KEY TERMS 及相应的中文含义。 5. 课后阅读：阅读教材 11.1 P522~532

CHAPTER Four ： File Management, Virus Protection and Backup 第 4 章：文件管理、病毒防护和备份.

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CHAPTER Four ： File Management, Virus Protection and Backup 第 4 章：文件管理、病毒防护和备份.

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Presentation on theme: "CHAPTER Four ： File Management, Virus Protection and Backup 第 4 章：文件管理、病毒防护和备份."— Presentation transcript:

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