13 what extensions software applications can have. Determine file type and extension. File extensions in Windows. The Additional File Anti-Virus settings window

A file extension or file name extension is a suffix at the end of a computer file. It is usually two to four characters long. If you've ever opened a document or viewed an image, you've probably noticed these letters at the end of your file.

Screenshot of various extensions

File, what is a file, you suddenly ask? And this, in our case, is just data of a certain type stored on an electronic medium.

What is the filename extension used for?

File extensions are used by the operating system to determine which applications are associated with file types - in other words, which application opens when you double-click on a file.

For example, a file named "awesome_picture.jpg" has a "jpg" extension. For example, when you open this document in Windows, the operating system looks for any JPG-related application, opens that application, and loads the file. A extension .m4r applied

What are the types of extensions?

There are many different types of file extensions - too many to list in one article - but here are a few examples of common file extensions you may see on your computer:

DOC/DOCX: Microsoft Word document. DOC was the original extension used for Word documents, but Microsoft changed the format when Word 2007 debuted. Word documents are now based on the XML format, hence the addition of an "X" at the end of the extension.

XLS/XLSX: - Microsoft Excel spreadsheet.

PNG: Portable Network Graphics, lossless image format.

HTML/HTML: HyperText markup format for creating web pages on the Internet.

PDF: A portable document format created by Adobe and used to support formatting in distributed documents.

EXE: executable format used for programs that you can run.

And, as we said, it's just a small number of file extensions. There are literally thousands of them.

It's also important to know that there are file types that are inherently dangerous and can be dangerous. Typically, these are executable files that can run certain types of code when you try to open them.

Do not open files if they come from an untrusted source.

Under the spoiler find 50+ file extensions that are potentially dangerous for Windows

Programs

EXE is the program's executable file. Most applications that run on Windows are .exe files.

PIF is a program information file for MS-DOS programs. Although .PIF files are not supposed to contain executable code, Windows will treat .PIF files the same way as .EXE files if they contain executable code.

APPLICATION - An application installer deployed using Microsoft's ClickOnce technology.

GADGET is a gadget file for the Windows Desktop Gadget technology introduced in Windows Vista.

MSI is a Microsoft installation file. They install other applications on your computer, although applications can also be installed by .exe files.

MSP - Windows Installer patch file. Used to patch applications deployed in .MSI files.

COM - The original program type used by MS-DOS.

SCR - Windows Screen Saver. Windows screensavers may contain executable code.

HTA is an HTML application. Unlike HTML applications that run in browsers, .HTA files run as robust applications without a sandbox.

CPL - Control Panel File. All utilities found in the Windows Control Panel are .CPL files.

MSC - Microsoft Management Console file. Applications such as the Group Policy Editor and the Disk Management tool are .MSC files.

JAR - .JAR files contain executable Java code. If you have the Java Runtime Environment installed, .JAR files will run as programs.

Scenarios

BAT is a batch file. Contains a list of commands that will run on your computer if you open it. Originally used MS-DOS.

CMD is a batch file. Similar to .BAT, but this file extension was introduced in Windows NT.

VB, .VBS - VBScript file. Executes its included VBScript code if you run it.

VBE - Encrypted VBScript file. Similar to a VBScript file, but it's not easy to determine what the file will do if you run it.

js - JavaScript file. .JS are commonly used by web pages and are safe when run in web browsers. However, Windows will run .JS files outside of a non-sandboxed browser.

JSE - Encrypted JavaScript file.

WS , .WSF - Windows script file.

WSC, .WSH - Windows Script and Windows Script Host script files. Used in conjunction with Windows script files.

PS1 , .PS1XML , .PS2 , .PS2XML , .PSC1 , .PSC2 - Windows PowerShell script. Executes PowerShell commands in the order specified in the file.

MSH , .MSH1 , .MSH2 , .MSHXML , .MSH1XML , .MSH2XML - Monad script file. The monad was later renamed to PowerShell.

Labels

SCF - Windows Explorer Batch File. Can pass potentially dangerous commands to Windows Explorer.

INF is a text file used by AutoRun. If run, this file could potentially launch dangerous applications that it comes with or pass dangerous options to programs included with Windows.

Others.REG - Windows registry file. .REG files contain a list of registry entries that will be added or removed if you run them. A malicious .REG file can remove important information from your registry, replace it with unwanted data, or add malicious data.

Office Macros

DOC, .XLS, .PPT - Microsoft Word, Excel and PowerPoint documents. They may contain malicious macro code.

DOCM , .DOTM , .XLSM , .XLTM , .XLAM , .PPTM , .POTM , .PPAM , .PPSM , .SLDM. New file extensions introduced in Office 2007. The M at the end of a file extension indicates that a document contains macros. For example, a .DOCX file does not contain macros, but a .DOCM file can contain macros.

This is not an exhaustive list. There are other types of file extensions - such as .PDF - that have a number of security issues. However, for most file types above, there are none. They exist to run arbitrary code or commands on your computer.

What should I do if I don't see file extensions on my computer?

By default, Windows shows file extensions. For a while - in Windows 7, 8 and even 10 - this was not true, but luckily they changed the default settings.

We say that showing file extensions is not only useful, but also safer. Without showing the extensions, it's hard to tell if that PDF you're viewing (for example) is really a PDF and not some malicious executable plot.

If file extensions don't show up in Windows, it's easy enough to get that information back. From any file explorer window, simply select View ⯮ Options ⯮ Change Folder and search options.

screenshot of how to control the visibility of file extensions in Windows

In the Folder Options window, on the View tab, select the Hide extensions for known file types check box.

On macOS, file extensions are not displayed by default. The reason for this is that macOS doesn't really use extensions the way Windows does (which we'll talk more about in the next section).

However, you can do macOS file extensions and that's probably not too bad. With Finder open, simply go to Finder⯮ Preferences⯮ Advanced and then check the "Show all file extensions" box.

How do macOS and Linux use file extensions?

So we've talked about how Windows uses file extensions to find out what type of files it's dealing with and what application to use when opening a file.

Windows knows that the file named readme.txt is a text file because of this TXT file extension, and it knows how to open it with the default text editor. Remove this extension and Windows will no longer know what to do with the file.

While MacOS and Linux still use file extensions, they don't rely on them like Windows does. Instead, they use something like MIME and creator codes to determine what the file is. This information is stored in the header of the file, and both macOS and Linux use this information to determine what type of files they are dealing with.

Since file extensions are not actually required on macOS or Linux, you could very well have a valid file without the extension, but the OS can still open the file with the correct program due to the file information contained in the file's header.

What happens if I change the file extension?

Based on what we just talked about in the previous section, what happens when you change your file extension depends on which operating system you are using.

On Windows, if you remove a file extension, that operating system no longer knows what to do with that file. When you try to open the file, Windows will ask you which application you want to use. If you change the extension say you renamed the file from "coolpic.jpg" to "coolpic.txt" -Windows will try to open the file in the application associated with the new extension and you will get an error or an open but useless file.

In this example, Notepad (or any other default text editor) opened our "coolpic.txt" file, but it's just garbled jumbled text.

For this reason, Windows warns you when you try to change a file extension and you must confirm the action.

If you're using macOS, something similar happens. If you try to change the file extension, you will receive a warning.

If you change the extension to something else, macOS will try to open the file in the app associated with the new extension. And you will get an error message or a malformed file - just like in Windows.

Unlike Windows, if you try to remove a file extension in macOS (at least in Finder), macOS simply appends the same extension back using the data from the file's MIME type.

If you really want to change the file type - for example, you would like to change an image from JPG to PNG format - you will need to use software that can actually convert the file.

How to change the program that opens a file

Whenever you install an application that can open a specific type of file, that application and file extension are registered with your operating system. It is possible that multiple applications may open the same file.

You can launch the application and then upload any supported file type to it. Or you can right-click on a file to open its context menu and select an available application there.

For example, in the image below, you can see that we have several image applications on our Windows system that can open the "coolpic.jpg" file that we have right-clicked.

However, there is also a default application associated with each extension. This app opens when you double-click on a file, and on Windows, it's the app that appears at the top of the list you get when you right-click on a file (pictured above).

And you can change this default application. Just go to Settings ⯮ Applications ⯮ Default apps ⯮ Select default apps by file type. Scroll through the (very long) list of file types to find the one you want, then click its associated application on the right to change it.

And you can do the same on macOS. Just select the file of the type you want to change and choose File > Get Info from the main menu. In the Info window that appears, navigate to the "Open With" section, and then select your new application from the drop-down menu. Easy enough.

Now you know what a file extension is and how to change it.

Format in computer science is a certain standardized structure of an information object.

• File format is a description of the data structure in a computer file.
  • — format for storing text data.
  • - formats for storing graphic information - photographs and drawings.
  • — formats for storing sound files.
  • - video information storage formats (also Screen aspect ratio: 4:3, 14:9, 16:9) (also see List of file formats - a list of some file formats)
  • An open format is a public (its description is not closed) specification for storing digital data.

(Material from Wikipedia - the free encyclopedia)

Now more or less familiar words are beginning to occur, unless of course they read it.

What is the file format and file types?

So let's continue.

We have created with you text format file , in which information was recorded by copying it from the Internet. Now we can open this file at any time, see what is written there, maybe fix something or add (edit) and then save.

Tree sticks, you say. Well, how much can you procrastinate the same thing. You can go on, in principle, no longer chew. In principle, yes, but since I, very often, hear a question like, how to open file format file, then all the same, I will explain this topic in more detail so that you do not have any questions left.

After all, if you figure out what is incomprehensible here? Text he and in Africa text.

For us, yes, but not for the computer. The computer doesn't care, the picture is the president or the recipe for pancakes, our favorite song or the latest masterpiece of cinema.

The fact is that the computer "knows" and "performs operations" with only two digits - "0" and "1" (zero and one). All. He knows nothing more, like a piece of iron. Yes, he doesn't need it. For him, this is quite enough. (By the way, this is digital format .)

For him, for a computer, maybe enough, but not for us. Agree that for us to contemplate zeros and ones is not at all interesting. Give us a meaningful text or a beautiful picture, we won't agree to anything less. Well, that's right.

Yes, there are only two numbers - "0" and "1". But their combinations can be billions.

For example, if we take a simple text, then for a computer each character is strictly defined in binary form , i.e. any character or letter has a certain combination of zeros and ones.

For example, the English (Latin) letter "A" in binary form looks like "01000001" (occupies 1 byte or 8 bits), and the Russian (Cyrillic) letter « A « in binary it looks like "11010000 10010000" (occupies 2 bytes or 16 bits).
Remember how many bytes our pancake recipe from the first part of the article “weighs”? In my case, it was 507 bytes (Your may differ from mine, but it doesn't matter now).

Let's see how the computer "sees" our recipe for pancakes.

I did not begin to spread it all, there are 5 or 6 more times for as many. Yes, and it is not necessary. The important thing is how the computer "sees" our information and how it is recorded in it.

But the program (application) "Notepad" "stupidly" reads this information from where we wrote it down and "stupidly" displays this information to us, converting it into a form convenient for us, on the monitor screen. Since the file contains simple information in the form of letters and numbers (text format), we have no problems with the perception of this information. And the speed of displaying such “small things” on the monitor, one might say, is “mad”.

I wrote the word "stupidly" not by chance, and we'll talk about it later. But from a simple text editor "Notepad" more, to be honest, is not required.

I hope you understand everything, and questions how to open file type file, you will no longer have.

All. Moving on to more complex formats .

What are the types of files and how to change the file format to another?

You probably remember that we had problems with saving the picture. To do this, there are more "powerful" programs (applications) that can save text, pictures (images), and tables - and they can do a lot of other things.

To further explain the concept of "format", I will use the Microsoft Office Word text editor (link to the lessons with the Word) from the Microsoft Office software package. This is a rather powerful and friendly "monster", which can easily store anything (well, almost everything) in itself.

Let's go back to the site page where we copied the recipe for pancakes and copy this fragment again to the clipboard, as we did in the 1st part of the article.

That's it, the text with the image on the clipboard and let it “sit” there for now.

Let's create a Microsoft Word file (Microsoft Word). In principle, you can create it in the same way as we created the text file. But let's create it a little differently (in the future, you will already be able to decide for yourself which way it will be more convenient for you to do this).

We press sequentially with the left mouse button: Start - All Programs - Microsoft Office - Microsoft Office Word 2003, as shown in the figure.

You will see a text editor window "Microsoft Word" (Often the text editor "Microsoft Word" is called a "word processor" to emphasize its great features, i.e. this text editor allows you to work not only with text, but also with graphics, tables etc. This has nothing to do with the processor of the computer itself).

Now we paste into the file we created the content that is "languishing" in the clipboard. To do this, right-click on the white field, then in the menu that appears, move the mouse pointer to the "Insert" menu item and press the left mouse button, as shown in the figure.

All. We copied the recipe we needed from the Internet, and even with a picture. And the whole thing looks pretty nice.

Let's save all this to the desktop (I use saving files to the desktop solely for clarity. Actually, I don’t recommend doing this in the future. It’s best to create a couple of thematic folders on the desktop, for example, “My recipes”, “My photos". Moreover, inside the folders you can create more folders (subfolders) by subject. For example, in the "My Photos" folder, create folders "On Vasya's barbecue", "How I rested in the Canary Islands". And immediately save everything to created folders.Believe me, save a lot of time and nerves).

To save, perform the following steps. Let's sum up pointer mouse and successively left-click the menu items, pop-up menu items and pop-up buttons as shown in the figure: "File" - "Save as ..." - "Desktop" - "Save".

In the "File name:" field, you can write any name you like (I wrote "Thin Pancakes Recipe". You can not write the .doc extension here, the program will substitute it itself if the "File Type:" field is set to "Word Document (*.doc)")

Here I specifically opened the list formats and their respective extensions (in the figure, the arrow points to this button) in which Microsoft Word can save the file. By default, the document is saved in the Microsoft Word format ("doc" document). You can scroll through this list with the slider.

But you can also save the document in another format, such as text, by selecting "Plain text (*.txt)" in the "File type:" field. For what? Well, for example, so that this file can be opened and read by the Notepad program (application). True, at the same time, Word can throw out warnings that, they say, you will lose all sorts of formatting elements, pictures, and something else. But if you don’t pay attention to all these “shouts”, then it will save the plain text in a text format file.

What would you understand how to change file type, let's, for clarity, save in two more formats. In text format and in a format that can be placed on a website page on the Internet.

In the first case, in the "File type:" field, select "Plain text (*.txt)" by clicking on this line with the left mouse button and then again with the left mouse button, click the "Save" button. Word will save our recipe with the name “Thin Pancakes Recipe”, adding the .txt extension to it. i.e. save in text format.

In the second case, in the "File type: « select "Web page in one file (*.mht; *.mhtml)" by clicking on this line with the left mouse button and then again with the left mouse button click the "Save" button. Word will save our creation with the name “Thin Pancake Recipe” by adding the .mht extension to it, that is. e. save as web pages.

3 new files appeared on the desktop with the same name "Thin Pancakes Recipe", but with different extensions and, accordingly, different icons (icons, pictograms).

In other words, we created three files of different formats with the same (for us) information. And these three "recipes" are opened by different programs (applications). That is, by clicking twice quickly on each of shortcuts(well, or by opening them with the “old-fashioned method” as I described in the previous part of the article), we get the following:

"Recipe for thin pancakes.txt" - by default it is opened, edited and saved by the Notepad program (application)

"Recipe for thin pancakes.doc" - by default it is opened, edited and saved by the program (application) "Microsoft Word"

“Thin pancake recipe.mht” - by default, it only opens (not edited) by the Internet Explorer program (browser), since this is a program only viewing , not editing.

Now if anything, you know how to change file format.

Comparing sizes of different file types?

Let's compare two files that are opened, edited and saved by different text editors by default - "Thin Pancakes Recipe.txt" and "Thin Pancakes Recipe.doc".

To do this, we will look at the properties of these files (For this, as you remember, you need to hover the mouse pointer over the shortcut, press the right mouse button, move the mouse pointer to the "Properties" menu item and left-click on it).

So, what happens (the sizes of your files may differ slightly from mine, but this is a topic for another conversation and this is not important in our case). A "text" document has a size of 511 bytes, while a "Word" document has 46,080 bytes (a picture of pancakes in a file takes up 23,226 bytes).

I call the calculator (“Start” - “All Programs” - “Standard” - “Calculator”) and start counting.

The size of a "Word" document is about 90 times larger than a "text" document. Thus, on our 10 GB G: hard drive, which we took as an example, will fit (roughly) 200 thousand Word documents, in contrast to 20 million text documents.

The comparison may be a little rough, but it illustrates very well how much disk space the same information takes, depending on the format in which it is recorded.

You can smile and sarcastically tell me: So what. Yes, I can’t “rive” so many documents in my life. Yes, and the hard drive on my computer is 500 GB, I don’t even feel like counting how much it will fit there. And in terms of documents, you will be absolutely right.

But the space that documents take up on our hard drive is actually a thousandth or maybe even a millionth of what is stored on our computer.

For example, one high-quality (HD) movie can take up 20 GB or more on your hard drive.

And one more interesting moment. Let's try to open a file in the Microsoft Word format with the Notepad program (application), which does not understand this format.

To do this, call the Notepad program. Moving the mouse pointer sequentially with the left mouse button, click "Start" - "All Programs" - "Accessories" - "Notepad".

In the program window that appears, do the following: with the left mouse button, select "File" - "Open" - "Desktop". In the "File type:" field, left-click, click on the "drop-down list" button and select "All files".

We have opened the file. But what do we see?

Yes, nothing interesting. The Notepad program "stupidly" opened to us what it read from the disk.

“Encoded” information by Microsoft Word can only be read by a program that “understands” the .doc format (there are such programs, except for Word_a itself), and our application, as you probably remember, only understands the text format.

I also wanted to tell in this part of the article about graphics, music and video files . But the article turned out to be a little long again, and I really wanted to bring the fundamental things to you.

As for graphic, music and video files, there are a lot of interesting things there, and I would like to tell you a little more about them. And, so as not to bore you anymore, I will talk about it in this article.

That's all. Good luck and creative success to all. 🙂

Format – specification of the structure of data recorded in a computer file. The format of a file is sometimes indicated in its name as a part separated by a dot (usually this part is called the filename extension, although this is not strictly speaking). For example, the name ending (extension) ".txt" is usually used to denote files containing only text information, and ".doc" - containing text information structured in accordance with the standards of the Microsoft Word program. Files whose contents correspond to one format (less commonly, one family of formats) are sometimes called files of the same type. Since the common concept of a file in computing is an unstructured sequence of bytes, computer programs that store structured data in files must somehow convert them to a sequence of bytes and vice versa (in OOP, these operations are called, respectively, "serialization" and "deserialization"; for textual information, the latter is also called "parsing" or "parsing"). The algorithm for this transformation, as well as the conventions for how various pieces of information are arranged within the file, constitute its "format". Different file formats may vary in the level of detail, one format may be an "add-on" to another, or use elements of other formats. For example, the text format imposes only the most general restrictions on the data structure. The HTML format sets additional rules for the internal structure of the file, but any HTML file is at the same time a text file.

Specifications

For many file formats, there are published specifications that detail the file format's structure, how programs should encode data to write to that format, and how to decode it when read. Most of these specifications are freely available, some are distributed for a fee. Sometimes companies may consider certain file formats as their trade secret and not publish them. A well-known example is the file formats of the Microsoft Office package. In some cases, the company that released the application simply doesn't feel the need to take the time to write a detailed specification. If a format specification is not available, reverse engineering must be done to make the program compatible with that format. In most or all countries, file formats are not protected by copyright laws. However, in some countries, algorithms used to encode data into a format may be protected by patents. For example, the widespread GIF format used a proprietary algorithm (patents expired in various countries in 2003-2004), which led to the development of an alternative PNG format.

Determining the file type

File type is information for quickly identifying the contents of a file by the operating system and the user without having to read the entire contents of the file. Thanks to this information, the user approximately knows the type of information contained in the file, and the operating system can be associated with a program for processing files of this type. In order to work correctly with files, programs must be able to determine their type. For historical reasons, different operating systems use different approaches to this task.

File name extension

Some operating systems, such as CP/M, DOS, and Microsoft Windows, use part of a file's name, i.e. "filename extension", to determine the type of a file. In older operating systems, these were three characters separated from the file name by a dot (in file systems of the FAT family, the name and extension were stored separately, the dot was added already at the OS level); on newer systems, the extension may simply be part of the name, in which case its length is limited only by the unused length of the name (which may be, for example, 255 characters). For example, HTML files may have the extension ".htm" or ".html". The user can freely change the file extension. Because many user shells use an extension to determine which program to open a file with, this can make the file unusable or even "lost" if the user forgets the original extension. Therefore, Windows Explorer hides extensions by default. This practice has a downside: since the file extension is not visible, you can trick the user into thinking that, for example, a file with the .exe extension is an image with a different extension. At the same time, an advanced user can use the ability to change the type assigned to a file by simply changing the extension in order to open it in another program without directly specifying it. This can be useful if the program does not provide for opening files with some extension, and the user knows that their format is suitable for processing in this program.

magic numbers

Another method, widely used in UNIX-like operating systems, is to store in the file itself some kind of "magic number" (signature) - a sequence of characters by which the file format can be identified. The term was originally used for a special set of 2-byte identifiers stored at the beginning of a file (this practice has migrated to other operating systems, such as MZ in MS-DOS), however, any sequence of characters specific to this format can be used as " magic number. To determine the format of a file, use the file command, which uses the file /usr/share/misc/magic

metadata

Some file systems allow you to store additional attributes for each file, i.e. "metadata". This metadata can be used to store information about the file type. This approach is used in Apple Macintosh computers. Metadata is supported by such modern file systems as HPFS, NTFS, ext2, ext3 and others. The disadvantage of this method is poor portability - when copying files between file systems of different types, metadata can be lost.

The data types defined by the MIME standard are widely used in various network protocols, but they are still rarely used in file systems.

The table below lists the most commonly used file formats today.

Bibliography.

Constitution of the Russian Federation. A comment. M.: Legal literature, 1994

Commentary on the Constitution of the Russian Federation. "Legal Literature". M.: 1994

Federal Constitutional Law “On Arbitration Courts in the Russian Federation”, Arbitration Procedure Code of the Russian Federation. M.: “Os-89”, 1995

Every file on a computer stores data of a certain type. For example, it can be textual information, program codes, an image, sound, or something else. Intuitively, you already understand what a file extension is. Therefore, today we will fill in the gaps in knowledge and try to delve deeper into the topic.

Definition

The extension is the second part of the filename after the dot. As a rule, it consists of 2-4 characters. This designation simplifies the operation of the operating system, telling it exactly what information is contained in the document and what program should be used to open the file.

When you install any new program, the Windows registry is updated with information about what formats it can work with. It is thanks to this that pictures open in special galleries, and music opens with the help of a multimedia player. If you wish, you can change the program that will be used to open files of a certain type.

Popular extensions

It is useful to know not only what a file extension is, but also what types of data are stored in different documents. Here is a list of the most common on Windows:

• Text: txt, .doc (.docx), .rtf.
• Web pages: .htm and .html.
• Archives: .zip, .rar.
• Images: .png, .bmp, .gif, .tiff.
• Audio: .mp3, .wav, .wma, .cda.
• Video: .avi, .wmv, .mpg (.mpeg), .MPEG-4, .wmv, .flv, .vob, .mdv, .swf.
• Presentations: .ppt (.pptx).
• Tables: .xls (.xslx).
• Fonts: .ttf, .otf.
• E-books: .pdf, .epub, .fb2, .djvu.
• Databases: .mdb, .accdb.
• Executable (launch or install programs): .exe, .bat.

Tip: when working with documents of unknown formats, the Russian-language service Open-File.ru is very helpful. Just type in the name in the directory search, and you will see the basic information: what data the document contains (image, text, etc.), what is the appropriate file extension program in which to open it.

Customizing the display of extensions

By default, the operating system automatically displays the document format next to its name. However, at any time you can make sure that file extensions in Windows are not displayed or, conversely, enable them. What do I need to do?

1. Go to "Control Panel".
2. Find the item it is called "Folder Options", and in Windows 8 and 10 - "Explorer Options".
3. In the window that appears, select the "View" tab.
4. Find the "Hide extensions for known file types" item in the "Advanced options" list and check the box next to it.
5. Click the "Apply" button and close the window.

Please note: if the file extension is disabled in Windows 7 or another version of the OS, you need to be more careful when renaming any documents. If you accidentally delete or change this postscript, the file will be impossible to open.

How to change the extension

Now that you know the file extension, let's talk about how it can be converted. This is necessary if, for example, you want to open a file intended for one program in another application.

Strictly speaking, there are two ways to do this:

1. Rename the document - just enter the one you need instead of the "native" extension (for example, .html instead of .txt).
2. Use special converter programs. Some are installed on a PC, others are available online. They are resorted to if you need to completely change the encoding of the document.

If you want information to be displayed as correctly as possible in another program, it is better to use full-fledged converters.

Of the popular services of this type, Convertio can be noted. This online converter supports most common file extensions and also has a number of additional tools such as PDF compression and merging, a URL converter to extract music and videos from websites, and scanned text recognition.

How to change the program to open

And finally, consider the situation where you downloaded a new application and want to use it to work with certain documents. For example, change the standard photo viewer in Windows to Microsoft Office Picture Manager. How to do it?

1. Select the desired file and open the context menu (right mouse button).
2. Find "Open with" > "Choose another app".
3. Select the desired program in the list that appears and check the box next to "Always use this application ...".
4. Click OK.

This means that the system will now open such a file extension using the program that you have chosen. In Windows 8 and 10, if a suitable application is not found on the PC, you also have the option to find it in the Store.

Experienced PC users can say with confidence what a particular file is - a picture, music, program. This is not difficult if you know about such a thing as a file extension. Using this knowledge is the most common way to determine the type of data that has been stored in a file, and an additional way to protect yourself from viruses. At its core, an extension is a few characters added to a filename that are used to identify its format.

OS Windows file display is disabled by default. Of course, this eliminates the need to view some unnecessary information, but at the same time, many users are guided only by the name of the file, open everything in a row, without thinking about the possible danger. You can enable the display of extensions in the Control Panel. To do this, go to "Folder Options" and uncheck the "View" tab next to the corresponding line.

The best protection for your computer is a good antivirus program. However, even the highest quality antivirus can make a mistake or simply not have time to bring the virus into its filters. Therefore, in addition to special programs, for the security of the computer, you must use your own knowledge. For example, if you receive an email with a file from a person you don't know, be sure to check the extension before opening it. If it is not on the safe list, it must be checked with an antivirus program. Dangerous file types may contain viruses or spyware that can harm both your computer programs and important information stored on it. The most dangerous extensions are considered .exe- program files and macros. Of course, if you received the expected letter by e-mail, then there is nothing to be afraid of. But when receiving a letter from an unreliable source, it is better to play it safe and first check the file for viruses.

In order to protect your computer from viruses, you need to know exactly what a particular extension is. The programs use the following formats:

Script files are also executable files, but their difference is that they are not launched independently, but by some program or service. The most dangerous scripts are files with the extension .cmd, .vbs And .bat. For example, even without special software, using a regular notepad, you can write a script with the .bat extension, which will connect to an ftp server at startup, download and run a virus, while bypassing the protection of some antivirus programs.

Scripts

Script files include extensions such as:

Labels

As for labels, the following formats are used here:

Additionally

In addition, you should be careful about formats such as .dotm, .docm, .xlsm, .xlam, .xltm, ppsm, .ppam, .sldm, .potm And .pptm. The presence of the letter "m" at the end indicates that the document contains macros. You should also be careful about the Windows registry file extension - .reg, so as not to lose important information that is in it and not add dangerous data there.

To the formats of such, at first glance, safe files, such as .txt(text files) and .jpg, .png And .gif(image files), you should still be careful. Some viruses use double file extensions to make malicious formats appear safe. For example, if you received an email with the file foto.jpg.exe, then when you open it, the operating system will select the extension located to the right. This will open an .exe file, which is an executable program that can infect a computer with a virus. Remember that legitimate files rarely have double extensions, so it's best not to open or download data in such formats.

This information is very important, as it will help protect your computer from viruses, and you - from unnecessary problems!