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Application-based file management
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Applications, such as word processing software or graphics software, typically provide a way to open files and save them in a specific folder on a designated storage device. Take a look at an example of the file management capabilities in a typical Windows application — Microsoft Word.
As you type the document, it is held in RAM. If you want to save the document, you click File on the menu bar, and then select the Save As option. The Save As dialog box opens and allows you to specify a name for the file and its location on one of your computer’s storage devices.
The difference between the two options is subtle, but useful. 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. If you want to save a new file without a name, your application displays the Save As dialog box, even though you selected the Save option.
Windows explorer
As an example of a file management utility, take a closer look at Windows Explorer, a utility program bundled with the Windows operating system and designed to help you organize and manipulate the files stored on your computer.
The Windows Explorer window is divided into two “window panes” (see figure 5 on the following page).
In addition to locating files and folders, Windows Explorer provides a set of procedures that help you manipulate files and folders in the following ways:
- Rename
- Copy.
- Move. When you move a file, it is erased from its original location, so make sure you remember the new location of the file.
- Delete.
File management tips
The following tips pertain to managing files on your computer.
-Use descriptive names. Give your files and folders descriptive names, and avoid using cryptic abbreviations.
-Maintain file extensions. When renaming a file, keep the original file extension so that you can easily open it with the correct application software.
- Group similar files. Separate files into folders based on subject matter.
- Organize your folders from the top down. When devising a hierarchy of folders, consider how you want to access files and back them up.
- Do not mix data files and program files. Do not store data files in the folders that hold your software.
Fig. 5: The Windows Explorer window
- Don’t store files in the root directory. Although it is acceptable to create folders in the root directory, it is not a good practice to store programs or data files in the root directory of your computer’s hard disk.
- Access files from the hard disk. For best performance, copy files from floppy disks or CDs to your computer's hard disk before accessing them.
- Delete or archive files you no longer need. Deleting unneeded files and folders helps keep your list of files from growing to an unmanageable size.
- Be aware of storage locations. When you save files, make sure the drive letter and folder name specify the correct storage location.
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- Back up! Back up your folders regularly.
Physical file storage
Before a computer can store a file on a disk, CD, or DVD, the storage medium must be formatted. The formatting process creates the equivalent of electronic storage bins by dividing a disk into tracks and then further dividing each track into sectors. Tracks and sectors are numbered to provide addresses for each data storage bin. The numbering scheme depends on the storage device and the operating system. On floppy, Zip, and hard disks, tracks are arranged as concentric circles; on CDs and DVDs, one or more tracks spiral out from the center of the disk.
To speed up the process of storing and retrieving data, a disk drive usually works with a group of sectors called a cluster or a “block”. The number of sectors that form a cluster varies, depending on the capacity of the disk and the way the operating system works with files. 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 index file. If your computer uses the FAT32 file system, for example, this index file is called the File Allocation Table (FAT). If your computer uses NTFS, it is called the Master File Table (MFT).
When you save a file, your PC’s operating system looks at the index file to see which clusters are empty. It selects one of these empty clusters, records the file data there, and then revises the index file to include the new file name and its location.
Comprehension check. Indicate the paragraph where the following ideas are found in the text.
1. It is preferable to maintain file extensions and not to store files in the root directory.
2. There is a slight difference between the Save option and the Save As option.
3. A special index file is required to keep track of a file’s location.
4. This program is related to the Windows operating system and exemplifies a file management utility.
5. The way to open and save a file on a specified storage medium depends on software applications.
6. Apart from locating files, it enables users to rename, copy, move and delete them.
Vocabulary practice
1. Match up the words that are opposite in meaning.
save distinct
empty display
additional include
subtle erase
hide basic
retrieve full
2. Fill in the blanks choosing out of the variants given.
1. To make storing and finding data fast, a disk drive deals with a … which is a group of sectors.
a) track b) bin c) cluster d) junction
2. You had better … cryptic abbreviations in files and folders.
a) give b) avoid c) access d) accept
3. You can avoid growing your list of files to an unmanageable size by … unnecessary files and folders.
a) saving b) deleting c) renaming d) moving
4. File … facilitates the process of organizing and manipulating your computer-based files.
a) location b) extension c) performance d) management
5. The operating system revises the index file to … the new file name and its location.
a) erase b) include c) number d) exclude
6. … a file is stored on a disk, CD, etc., the storage medium should be formatted.
a) before b) after c) while d) since
7. The pattern of … tracks and sectors is dependent on the storage medium and your PC’s operating system.
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a) dividing b) selecting c) numbering d) arranging
3. Make three-word combinations using the words in columns and then fill in the gaps in the following sentences.
A: file B: sign C: option
save storage utility
master management table
data file bin
plus as icon
1. If you want to select a name and a storage device for a file, the … should be used.
2. … are designated addresses by numbering tracks and sectors.
3. A special … provided by the operating system helps you manage your files efficiently.
4. The … is used to display the next level of your computer’s hierarchy of storage devices and folders.
5. The … is the index file supported by the NFTS file system.
4. Fill in the gaps in the text.
File ___ provides any procedure that can help you organize your computer-based files so that you can find and use them more ___. File management uses tools provided with a software program to open and save files. Additional tools might enable you to ___ new files and folders, rename files, and delete them. The Save and Save As ___ boxes are examples of these file management tools.
Before a computer stores data on a disk, CD, or DVD, it creates the equivalent of electronic storage ___ by dividing the disk into ___, and then further dividing the disk into ___. This dividing process is referred to as ___. Each sector of a disk is numbered, providing a storage address that the operating system can track. Many computers work with a group of sectors, called a ___, to increase the efficiency of file storage operations.
Speaking. Discuss the following questions.
1. What does file management mean?
2. How does a software application help users manage files?
3. What is the difference between the Save option and the Save As option?
4. What is the example of a file management utility?
5. What is Windows Explorer designed for?
6 What can be done with the files and folders that are listed in Windows Explorer?
7. What file management tips should be followed while manipulating files?
8. What does the formatting process involve?
9. What is a cluster?
10. Is a file system’s primary or secondary task to keep track of which clusters keep data and which clusters don’t?
11. How does the operating system use an index file to help you save a file?
Text C
Pre-reading. Match the meaning of the following English words with their Russian equivalents.
| computer virus | вирусная подпись |
| malicious code | бот |
| boot sector virus | компьютерный вирус |
| macro virus | «Троянский конь» |
| trigger event | переключающее (триггерное) событие |
| Trojan horse | контрольная сумма |
| keylogger | клавиатурный шпион |
| bot | макровирус |
| antivirus software | вирус сектора загрузки |
| checksum | вредоносный код |
| virus signature | антивирусное программное обеспечение |
Reading. Read the text and try to guess the meaning of the words in bold. Check your variants in the dictionary.
Computer Viruses
Viruses are one of the biggest threats to the security of your computer files. In 1981, there was one known computer virus. Today, the count exceeds 100,000. Between 900 and 1,300 new viruses appear every month.
A computer virus is a set of program instructions that attaches itself to a file, reproduces itself, and spreads to other files. The term “computer virus” is often used to refer to any malicious code or software that invades a computer system. The term malicious code (sometimes called “malware”) refers to a program or set of program instructions designed to surreptitiously enter a computer and disrupt its normal work. Many types of malicious code, including viruses, worms, and Trojan horses, are created and unleashed by individuals referred to as “hackers” or “crackers”.
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Viruses spread when people distribute infected files by exchanging disks and CDs, sending e-mail attachments, exchanging music on file-sharing networks, and downloading software from the Web. Many computer viruses infectfiles executed by your computer – files with extensions such as.exe,.com. or.vbs. When your computer executes an infected program, it also executes the attached virus instructions.
A virus can be classified as a file virus, boot sector virus, or macro virus. A file virus infects application programs, such as games. A boot sector virus infects the system files your computer uses every time you turn it on. These viruses can cause widespread damage to your computer files and recurring problems. A macro virus infects a set of instructions called a “macro” – a miniature program that usually contains legitimate instructions to automate document and worksheet production. When you view a document containing an infectedmacro, the macro virus duplicates itself into the general macro pool, where it is picked up by other documents. In addition to replicating itself, a virus might deliver a payload, which could be as harmless as displaying an annoying message or as devastating as corrupting the data on your computer’s hard disk. A trigger event, such as a specific date, can unleash some viruses. For example, the Michelangelo virus triggers on March 6, the birthday of artist Michelangelo.
A Trojan horse (sometimes simply called a “Trojan”) is a computer program that seems to perform one function while actually doing something else. Trojan horses are notorious for stealing passwords using a keylogger – a type of program that records your key-stroke.
Any software that can automate a task or autonomously execute a task when commanded to do so is called an intelligent agent. Because an intelligent agent behaves somewhat like a robot, it is often called a bot. Like a spider in its web, the person who controls many bot-infested computers can link them together into a network called a botnet. Botnets as large as 400,000 computers have been discovered by security experts.
Malicious Code Trends
| Date | Threats | Trends |
| Cloner | The first known virus begins to spread. Cloner infects files on disks formatted for Apple II computers. The prevalence of disk-borne viruses continues well into the1990s with Jerusalem (1987), Michelangelo (1992), and others. | |
| Internet Worm | The first major worm attack over the Internet sets the stage for today's prolific crop of mass-mailing worms. | |
| Back Orifice | First Trojan horse designed to allow a remote hacker to gain unauthorized access to a computer. | |
| Melissa | Macro viruses, such as Melissa and l.aroux, are prevalent for several years and cause trouble by infecting Microsoft Word and Excel files. | |
| Love Letter | One of the fastest spreading mass-mailing worms. Followed by Sobig, Blaster, and MyDoom (2004). | |
| Code Red | Worms designed for Denial of Service attacks gather steam. Code Red, which targeted the White House, is followed by Blaster (2001) and Slammer (2003). | |
| Klez | Klez is a mass-mailing worm that is particularly difficult to eradicate. Because the “From” address is spoofed, it is almost impossible to locate infectedcomputers. | |
| 20Most notebook computers are equipped with several USB ports. 03 | Mimail | Social engineering takes center stage and users are confused by fake e-mails from seemingly legitimate companies, such as PayPal, Microsoft, and Wells Fargo. |
| Sasser Netsky Xombe MyDoom, Zafi Bagle | Worms, such as Sasser, begin to emerge that infect computers without user interaction, such as opening an infectede-mail attachment. Mass-mailing worms are still most prevalent. Worms that spread over instant messaging and handheld devices begin to emerge. | |
| Mytob Zotob Rbot | Bots become one of the biggest security problems. Arriving as e-mail attachments, links embedded in e-mail messages, or from infected banner ads, bots install themselves on unprotected computers, which can then be controlled by unauthorized hackers and commandeered into botnets that launch spam and Denial of Service attacks. |
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These are the top three steps you can take to prevent your computer from becoming infected:
- Use antivirus software on every computing device you own.
- Keep software patches and operating system service packs up to date.
- Do not open suspicious e-mail attachments.
Antivirus software is a type of utility software that can look for and eradicate viruses, Trojan horses, bots, and worms. This essential software is available for handheld computers, personal computers, and servers. Popular antivirus software for personal computers includes McAfee VirusScan, Norton AntiVirus, and F-Secure Anti-Virus.
Antivirus software uses several techniques to find viruses. As you know, some viruses attach themselves to an existing program. The presence of such a virus often increases the length of the original program. 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.
To counter early antivirus software, hackers became more cunning. They created viruses that insert themselves into unused portions of a program file without changing its length. Antivirus software developers fought back. They designed software that examines the bytes in an uninfected application program and calculates a checksum. A checksum is a number calculated by combining the binary values of all bytes in a file. Each time you run an application program, antivirus software calculates the checksum and compares it with the previous checksum. If any byte in the application program has changed, the checksum will be different, and the antivirus software assumes that a virus is present.
Today’s viruses, Trojan horses, bots, and worms are not limited to infecting program files, so modern antivirus software attempts to locate them by searching your computer’s files and memory for virus signatures. A virus signature is a section of program code, such as a unique series of instructions, that can be used to identify a known malicious program, much as a fingerprint is used to identify an individual.
Comprehension check. Choose the ending for each sentence from the two versions given.
| 1. Worm named Code Red was targeted | a) White House; b) Bank of Scotland. |
| 2. Any program designed to enter a computer and disrupt its normal operations is called | a) malicious code; b) utility. |
| 3. Many types of malicious codes are created by | a) the computer itself; b) individuals referred to as “hackers”. |
| 4. A boot sector virus infects the system files your computer uses | a) every time you turn it on; b) when you are connected to the Internet. |
| 5. A change in the length of a program from one computing session to the next | a) indicated the possible presence of a virus; b) is a result of operation system work. |
| 6. A checksum is | a) a number calculated by combining the binary values of all bytes in a file; b) the cost of an antivirus program. |
Vocabulary practice
1. Which word does not belong to the group?
a) virus, worm, Trojan horse, bot, file, botnet;
b) distribute, download, automate, infect, view, execute;
c) duplicates, instructions, infects, invades, behaves, spreads;
d) spider, programmer, hacker, user, server, developer;
e) individual, general, normal, personal, analytical, digital.
2. Fill in the blanks choosing from the variants given.
1. Does the term computer virus refer to any malicious code that … (makes up/invades) a computer system?
2. When your computer executes an infected program it … (executes / deletes) the attached virus instructions.
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3. A trigger event, such as a specific date, can … (kill/destroy/unleash) some viruses.
4. Love letter is one of the … (slowest/fastest) spreading mass-mailing worms of all time.
5. Hackers created viruses that insert themselves into … (used/unused) portions of a program file without changing its length.
3. Transform the given sentences using the word(s) in brackets without any change in meaning.
1. A computer virus is a set of programs that attaches itself to a file (connecting).
2. If a document contains an infected macro, the macro virus duplicates itself into the general macro pool, where it is picked up by other documents (doubles, selected).
3. A virus might deliver a payload which could be both harmless and devastating (do no harm, corrupt).
4. Software that can automate a task when commanded to do so is called an intelligent agent (is able, is instructed).
5. A trigger event, such as a specific date, can unleash some viruses (particular, release).
6. Trojan horses are notorious for stealing passwords using a keylogger – a type of program that records your key-strokes (known, a sort).
4. Fill in the gaps in the text.
A computer virus is a set of program instructions that attaches itself to a file, reproduces itself, and spreads to the other files. You might encounter several types of viruses. A virus that attaches itself to an application program, such as a game utility, is known as a ___ virus. A boot ___ virus infects the system files your computer uses every time you turn it on. A ___ virus infects a set of instructions that automates document and worksheet production.
A Trojan horse is a computer program that seems to perform one function while actually doing something else. Such programs are notorious for stealing ___, although some delete files and cause other problems.
___ software can help prevent viruses from invading your computer system and can root out viruses that that take up residence. This software typically scans for a virus ___ and is sometimes referred to as virus scanning software.
Speaking. Discuss the following questions.
1. What is a computer virus?
2. How do viruses spread?
3. Are there different kinds of viruses?
4. What is a Trojan horse? What is a bot?
5. What is a botnet?
6. How can you avoid viruses and worms?
7. What is antivirus software? How does it work?
Text D
Reading. Read the text and try to guess the meaning of the words in bold. Check your variants in the dictionary.
Data Backup
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