"File archive" - Server file system. FTP client. File exchange program - ftp. Server file system 2. User. FTP protocol. Server Protocol Interpreter 1. Server data transfer program 2. Data. Data channel. Using archives. The server usually starts when the computer boots. FTP data exchange takes place over a TCP channel.
"Image in Word" - Working with pictures in the text editor Microsoft Word. Selection of lines, arrows, shapes. Hello! Reset pattern settings. Consider the Draw panel menu. Actions with pictures. Change in brightness. Exercise. Two buttons on the Drawing panel will help you add a picture, add a picture. To create the shadow of an object.
"Image" - Compress images. Representation of images. Omit binary encoding. Exercises. Next, check adjacent areas for uniformity and merge where possible. Search in the image database. Then restore (decode) the image. Database structures for images. Sample database architecture for images.
“The body is called a cylinder” - The height of the cylinder is 8 m, the radius of the base is 5 m. The cylinder is intersected by a plane so that it is a square in cross-section. Solution: Project "Mathematics in the profession" Chef, pastry chef ". Problem number 3. Cylinder. A regular hexagonal prism is inscribed in the cylinder. Let's find the length (h) of the perpendicular OK. 4) By the condition AB = A "B" = M "= 8. In a right-angled triangle AOK, the legs AK = 4. Then, by the Pythagorean theorem, h = OK = = = 3 m.
"Creation of graphic images" - The AutoShape button is intended for drawing various geometric shapes. Autoshapes. Comparative characteristics of raster and vector graphics. The position of the graphic in the text. Insert a picture from a file. Insert a picture from the Microsoft Office collection. Insert? Drawing? From a file. Insert a picture from the collection into the text.
"Computer graphics" - Raster graphics. Large amounts of data. Each point on the screen can have only two states - "black" or "white". Bitmap file formats. A pixel is the smallest element in a bitmap. Computer graphics. Color images can have different color depths (bits per point 4, 8, 16, 24).
Description of the presentation FILES AND FILE STRUCTURES COMPUTER AS A UNIVERSAL DEVICE by slides
Keywords logical name of external storage device file file naming rules directory root directory file structure file path full file name
Logical names of external storage devices Each external storage device that you connect to your computer has a logical name. In Windows OS, logical names of external memory devices are accepted, consisting of one Latin letter and a colon sign: for floppy disk drives (floppy disks) - A: and B: for hard disks and their logical partitions - C:, D: C (C :) D (D :) for optical drives - names that follow in alphabetical order after the name of the last available hard disk or hard disk partition DVD-RW drive (E :) A (A :) for flash memory connected to the computer - the name following the last name of the optical drive (for example, F :) Removable disk (F :)) Linux uses different rules for naming disks and their partitions. For example: logical partitions belonging to the first hard disk are named hda 1, hda 2, etc.; logical partitions belonging to the second hard disk are named hdb 1, hdb 2, etc.
A file is a named area of external memory. The file system is the part of the operating system that determines the way files are organized, stored and named on storage media. Document files are created and processed using application files. Document Application Graphic Text Application program. File. The file name consists of two parts, separated by a period: the actual file name and the extension. The actual name of the file is given by the user. The name extension is usually set by the program automatically when the file is created. File type Extension examples System file drv, sys Text file txt, rtf, docx, odt Graphic file bmp, gif, jpg, tif, png, pds Web page htm, html Sound file wav, mp 3, midi, kar, ogg Video file avi, mpeg Archive zip, rar Spreadsheet xls, ods Code (text) of the program bas, pas
Directories A directory is a named collection of files and subdirectories (subdirectories). The top-level directory is called the root directory. In Windows, root directories are designated by adding a "\" character to the logical name of the corresponding external memory device (A: \, C: \, D: \, E: \) In Linux, hard disk directories are not root directories. They are "mounted" in the mnt directory. Other external storage devices (floppy, optical, and flash drives) are “mounted” in the media directory. The mnt and media directories, in turn, are "mounted" into a single root directory, which is denoted by the "/" sign.
Disk file structure A disk file structure is a collection of files on a disk and the relationships between them. Simple file structures can be used for disks with a small (up to several dozen) number of files. ——— ——— ——— ——— ——— ——— —— A: \ d 1. txt d 2. txt d 3. txt d 4. txt d 5. txt
Disk file structure A disk file structure is a collection of files on a disk and the relationships between them. Hierarchical file structures are used to store a large (hundreds or thousands) number of files. A graphical representation of a hierarchical file structure is called a tree. —— —— —— —— —— —— —— —— —— E: \ video. avi graph. xls texts letter. txt numbers. txt image photo Biya. jpeg Katun. jpeg Onegin. doc aquarium. bmp melody. mp
File structure of a disk In Windows, directories on different disks can form several separate trees. In Linux, directories are combined into one tree that is common to all disks. Tree hierarchical structures can be displayed vertically and horizontally. bin home usr var ... shogun metohody bin etc doc ... -filename-with- text
Full file name File path - the names of all directories from the root to the one in which the file is located. On Windows, the file path begins with the logical name of the external storage device; a backslash is placed after the name of each subdirectory: E: \ images \ photo \ Katun. jpeg On Linux, the file path begins with the name of a single root directory; a forward slash is placed after the name of each subdirectory: / home / methody / text The path to the file and the file name in sequence form the full file name. There cannot be two files with the same full name.
The user worked with the directory C: \ Physics \ Tasks \ Mechanics. First, he went up one level, then went up one level again and after that went down to the Exam directory, which contains the Questions file. doc. What is the path to this file? Solution: Problem 1 C: Physics Problems. The user worked with the Mechanics catalog. Having climbed one level up, he ended up in the directory: Having climbed one level up, he ended up in the directory: After that, he went down to the Exam: Exam directory The full path to the file looks like: C: \ Physics \ Exam.
Problem 2 The teacher worked in the directory D: \ Lessons \ 7 grade \ Practical work. Then I went to a higher level in the directory tree, went down to the Presentations subdirectory and deleted the Introduction file from it. ppt. What is the full name of the file that the teacher deleted? Solution. The user worked with the catalog: Lessons grade 7. D: Practical work. Going up one level, he ended up in the catalog: Going down one level, he ended up in the Presentations catalog: Presentations. In the Presentation directory, he deleted the file Introduction. The full name of the remote file is D: \ Lessons \ 7th grade \ Presentations \ Introduction. ppt
Working with files Files are created using programming systems and application software. Basic operations with files: copying (a copy of a file is created in another directory or on another medium); moving (the file is transferred to another directory or to another medium, the original file is destroyed); renaming (renaming of the actual file name is performed); deletion (in the source directory, the object is destroyed). Opera è è è s wf. When searching for a file, you can use a file name mask - a sequence of letters, numbers and other characters allowed in file names, including:? (question mark) - means exactly one arbitrary character; * (asterisk) - means any (including empty) sequence of characters of arbitrary length. For example, by mask n? ... * files with arbitrary extensions and two-letter names starting with the letter "n" will be found.
Most importantly, File is a named area of external memory. The file name consists of two parts, separated by a dot: the actual file name and the extension. A directory is a named collection of files and subdirectories (subdirectories). The top-level directory is called the root directory. The file structure of a disk is a collection of files on a disk and the relationships between them. File structures are simple and multilevel (hierarchical). File path - the names of all directories from the root to the one in which the file is located. The file path and file name written in succession make up the full file name. The full filename is unique.
Questions and Tasks What is a file? What are the basic rules for naming files in the operating system installed on the computers in your classroom? What are the names of programs known to you that open files with the following extensions: txt, doc, bmp, rtf, arj. What are the logical names of the external storage devices on the computer to which you have access? What is a directory? Which directory is called the root? How can files be organized in external memory? What is the name of the graphical representation of the hierarchical file structure? What is the path to a file on disk? What is the fully qualified filename? List the main operations performed with files. File Pushkin. doc is stored on your hard disk in the POETRY directory, which is a subdirectory of the REFERENCES directory. The table contains fragments of the full file name: Recover the full file name and encode it in letters (write down the sequence of letters without spaces and commas). Sasha worked with the directory: D: \ LESSONS \ INFORMATICS \ PRACTICAL WORKS. He went up two levels, then went down to the ALGEBRA subdirectory and created the Quur file in it. txt. What is the full name of the file that Sasha created? The user worked with the directory: D: \ DOCUMENTS \ PHOTOS \ 2011 \ SPRING. First, he went up three levels, then went down to the EXAM catalog and after that went down to the INFORMATICS catalog. Specify the full path for the directory the user is in. 1) D: \ DOCUMENTS \ PHOTOS \ INFORMATICS 2) D: \ DOCUMENTS \ INFORMATICS \ EXAM 3) D: \ DOCUMENTS \ EXAM \ INFORMATICS 4) D: \ DOCUMENTS \ PHOTOS \ 2011 \ SPRING \ EXAM \ INFORMATICS check the box) those that match the mask? l * ck. * t? click. txt black. ppt lock. sts clock. tt blink. uta applock. stu blocker. htm elpack. ty blocker. html. From the list of names, select (check the box) those that DO NOT match the mask? l * ck *. *? : _ click. txt black. ppt lo 3 ck. sts clock. tt blink. uta applock. stu blocker. htm elpack. ty blocker. html. Please specify which of the following file names match the mask? ese * ie. ? t * 1.seseie. ttx 2.esenie. ttx 3.eseie. xt 4. sesenie. txt A B C D E F REFERENCES C: Pushkin \. doc POETRY
Anchor Synopsis A file is a named area of external memory. Each external memory device connected to the computer has a logical name (A: B: C: D: E: F:…) File search Full file name Address File name drive: \ path name. extension Simple Hierarchical File structure of the disk File type Example extensions System file drv, sys Text file txt, rtf, docx, odt Graphic file bmp, gif, jpg, tif, png, pds Sound file wav, mp 3, midi, kar, ogg Video file avi, mpeg Archive zip, rar Spreadsheet xls, ods
Keywords:
- logical name of the external storage device
- file naming rules
- catalog
- root directory
- file structure
- the path to the file
- full filename
2.4.1. Logical names of external storage devices
Several external memory devices can be connected to each computer. The main external memory device of a PC is a hard disk. If the hard disk has a large enough capacity, then it is divided into several logical partitions.
The presence of several logical partitions on one hard disk provides the user with the following benefits:
- You can store the operating system in one logical partition, and the data in another, which will allow you to reinstall the operating system without affecting the data;
- different operating systems can be installed on one hard disk in different logical partitions;
- maintenance of one logical partition does not affect other partitions.
Each external memory device connected to the computer, as well as each logical partition of the hard disk, has a logical name.
In the Windows operating system, logical names of external memory devices are accepted, consisting of one Latin letter and a colon:
- for floppy disk drives (floppy disks) - A: and B :;
- for hard drives and their logical partitions - C:, B:, E: it. etc .;
- for optical drives - names that follow alphabetically after the name of the last available hard disk or hard disk partition on the computer (for example, F :);
- for flash memory connected to a computer, the name following the last name of the optical drive (for example, G :).
The Linux operating system uses different rules for naming disks and their partitions. For instance:
- logical partitions belonging to the first hard disk are named hdal, hda2, etc.
- logical partitions belonging to the second hard disk are named hdbl, hdb2, etc.
2.4.2. File
All programs and data are stored in the computer's external memory as files.
The file system is the part of the operating system that determines the way files are organized, stored and named on storage media.
A file is characterized by a set of parameters (name, size, creation date, date of last modification) and attributes used by the operating system to process it (archive, system, hidden, read-only). The file size is expressed in bytes.
The file name, as a rule, consists of two parts, separated by a period: the actual file name and the extension. The actual name of the file is given by the user. It is recommended to do this sensibly, reflecting the content of the file in the name, although the user can specify an arbitrary set of characters as the name. The name extension is usually set by the program automatically when the file is created. Extensions are optional, but they are widely used. The extension allows the user, without opening a file, to determine its type - what kind of information (program, text, image, etc.) it contains. The extension allows the operating system to automatically open the file.
In modern operating systems, a file name can include up to 255 characters, and it is possible to use letters of national alphabets and spaces in it. The file name extension is written after a period and usually contains 3-4 characters.
On Windows, the following characters are not allowed in the file name: \, /,:, *,?, ", |. On Linux, these characters, except /, are allowed, although you should use them with caution, as some of them may have a special meaning, and also for reasons of compatibility with other OS.
The Linux operating system, unlike Windows, distinguishes between lowercase and uppercase letters in a file name: for example, FILE.txt, file.txt, and FiLe.txt are three different files in Linux.
The table lists the most common file types and their extensions:
The following file types are distinguished in Linux OS:
- regular files - files with programs and data;
- directories - files containing information about directories;
- links - files containing links to other files;
- device special files - files used to represent the physical devices of a computer (hard and optical drives, printer, speakers, etc.).
2.4.3. Catalogs
Each computer storage medium (hard disk, optical disk or flash memory) can store a large number of files. For the convenience of searching for information, files are grouped according to certain criteria into groups called directories or folders.
The directory also gets its own name. He himself can be part of another, external to him directory. Each directory can contain many files and subdirectories.
The top-level directory is called the root directory.
In Windows, any information medium has a root directory, which is created by the operating system without user intervention. Root directories are designated by adding a "\" (backslash) character to the logical name of the corresponding external memory device: A: \, C: \, D: \, E: \, etc.
In Linux, directories on hard drives or their logical partitions do not belong to the top level of the file system (they are not root directories). They are "mounted" in the mnt directory. Other external storage devices (floppy, optical, and flash drives) are “mounted” in the media directory. The mnt and media directories, in turn, are "mounted" into a single root directory, which is denoted by the "/" (forward slash) character.
2.4.4. File structure of the disk
File structures are simple and multilevel (hierarchical).
Simple file structures can be used for disks with a small (up to several dozen) number of files. In this case, the table of contents of the disk is a linear sequence of file names (Fig. 2.8). It can be compared to the table of contents of a children's book, which contains the names of the stories included in it and the page numbers.
Rice. 2.8.
Simple file structure
Hierarchical file structures are used to store a large (hundreds or thousands) number of files. Hierarchy is the arrangement of the parts (elements) of the whole in order from the highest to the lowest. The initial (root) directory contains first-level files and subdirectories. Each of the first-level directories can contain files and sub-directories of the second level, etc. (Fig. 2.9). In this case, the table of contents of the disc can be compared to the table of contents of our textbook: chapters are highlighted in it, consisting of paragraphs, which, in turn, are divided into separate paragraphs, etc.
Rice. 2.9.
Hierarchical file structure
The user, combining files into directories at his own discretion, gets the opportunity to create a convenient information storage system. For example, you can create separate directories for storing text documents, digital photos, ringtones, etc .; in the catalog for photos, combine photos by years, events, accessories, etc. Knowing which directory a file belongs to makes searching for it much faster.
A graphical representation of a hierarchical file structure is called a tree. In Windows, directories on different drives can form several separate trees; In Linux, directories are combined into a single tree, common to all disks (Figure 2.10). Tree hierarchical structures can be displayed vertically and horizontally.
Rice. 2.10.
Linux directory tree
2.4.5. Full file name
To refer to the desired file stored on a certain disk, you can specify the path to the file - the names of all directories from the root to the one in which the file is directly located.
On Windows, the file path begins with the logical name of the external storage device; a backslash is added after the name of each subdirectory. On Linux, the file path begins with the name of a single root directory; a forward slash is placed after the name of each subdirectory.
The file path and file name written in succession make up the full file name. There cannot be two files with the same full name.
An example of a fully qualified file name in Windows:
Е: \ images \ photo \ Katun.jpeg
An example of a fully qualified file name in Linux OS:
/ home / methody / text
Problem 1... The user worked with the directory C: \ Physics \ Tasks \ Kinematics. First, he went up one level, then went up one level again and after that went down to the Exam directory, which contains the Informatika.dos file. What is the path to this file?
Solution.
The user worked with the directory C: \ Physics \ Tasks \ Kinematics. Having climbed one level up, the user found himself in the C: \ Physics \ Tasks directory. Climbing one more level up, the user found himself in the C: \ Physics directory. After that, the user went down to the Exam directory, where the file is located. The full path to the file is: С: \ Physics \ Exam
Task 2... The teacher worked in the directory D: \ Lessons \ 8 grade \ Practical work. Then I went up one level in the directory tree, went down to the Presentations subdirectory and deleted the Introduction.ppt file from it. What is the full name of the file that the teacher deleted? Solution.
The teacher worked with the directory D: \ Lessons \ 8 grade \ Practical work. Climbing one level up, he found himself in the directory D: \ Lessons \ 8th grade. After that, the teacher went down to the Presentations directory, the path to the files of which looks like: D: \ Lessons \ 8 grade \ Presentations. In this directory, he deleted the file Introduction.ppt, the full name of which is D: \ Lessons \ 8 class \ Presentations \ Introduction.ppt
2.4.6. Working with files
Files are created using programming systems and application software.
In the process of working on a computer, the following operations are most often performed on files:
- copying (a copy of the file is created in another directory or on another medium);
- moving (the file is transferred to another directory or to another medium, the original file is destroyed);
- renaming (renaming of the actual file name is performed);
- deletion (in the source directory, the object is destroyed).
When searching for a file whose name is not known exactly, it is convenient to use the file name mask. A mask is a sequence of letters, numbers and other characters allowed in file names, among which the following characters can also occur: "?" (question mark) - means exactly one arbitrary character; "*" (Asterisk) - means any (including empty) sequence of characters of arbitrary length. For example, the mask n * .txt will find all files with the txt extension whose names begin with the letter "n", including the n.txt file. By mask n?. *, Files with arbitrary extensions and two-letter names starting with the letter "n" will be found.
The most important thing
The main external memory device of a PC is a hard disk. If the hard disk has a large enough capacity, then it is divided into several logical partitions. Each external memory device connected to the computer, as well as each logical partition of the hard disk, have logical names.
A file is a named area of external memory. The file name, as a rule, consists of two parts, separated by a period: the actual file name and the extension.
A directory is a named collection of files and subdirectories (subdirectories). The top-level directory is called the root directory.
The file structure of a disk is a collection of files on a disk and the relationships between them. File structures are simple and multilevel (hierarchical).
File path - the names of all directories from the root to the one in which the file is located. The file path and file name written in succession make up the full file name. The full filename is unique.
Questions and tasks
One computer can have multiple disk drives - disk devices. Each drive is assigned a one-letter name (followed by a colon), for example A :, B :, C :. Often on personal computers, a large-capacity disk built into a system unit (called a hard disk) is divided into partitions. Each of these partitions is called a logical drive and is named C :, D :, E :, etc. The names A: and B: usually refer to small removable disks - floppy disks (floppy disks). They can also be considered as names of disks, only logical ones, each of which completely occupies a real (physical) disk. Therefore, A :, B :, C :, D: are all the names of the logical drives.
The name of the logical drive containing the file is the first "coordinate" that identifies the location of the file.
3. File structure of the disk
The entire collection of files on disk and the relationships between them is called the file structure. Different operating systems can support different file structure organizations. There are two types of file structures: simple, or single-level, and hierarchical - multi-level.
A sibling file structure is a simple sequence of files. To find a file on disk, you just need to specify the file name. For example, if the tetris.exe file is located on the A: drive, then its "full address" looks like this: A: \ tetris.exe
Operating systems with a single-level file structure are used on the simplest educational computers equipped only with floppy disks.
A layered file structure is a tree-like (hierarchical) way of organizing files on disk. To facilitate understanding of this issue, we will use the analogy with the traditional "paper" way of storing information. In this analogy, the file is presented as a certain titled document (text, picture) on paper sheets. The next largest element in the file structure is called the directory. Continuing the "paper" analogy, we will think of a directory as a folder into which many documents, ie files, can be enclosed. The directory also gets its own name (imagine it is written on the cover of a folder).
The directory itself can be part of another directory external to it. This is the same as nesting a folder into another larger folder. Thus, each directory can contain many files and subdirectories (they are called subdirectories). The top-level directory that is not nested in any other directory is called the root directory.
The Windows operating system uses the term folder to refer to directory.
A graphical representation of a hierarchical file structure is called a tree.
In fig. 2.1 directory names are written in uppercase letters, and files are written in lowercase. Here in the root directory there are two folders: IVANOV and PETROV and one file fin.com. The IVANOV folder contains two subfolders PROGS and DATA. DATA folder - empty; there are three files in the PROGS folder, and so on. In a tree, the root directory is usually represented by the symbol.
Rice. 3.1. An example of a hierarchical file structure
