What do most file extensions in operating systems mean?
The file extension (filename extension), also known as the file suffix, is a mechanism used by the operating system to mark file types. Normally, an extension follows the main file name, separated by a delimiter. The extension can be thought of as metadata for a type.
Filename Extension (or extended file name, suffix name) is a mechanism used by early operating systems (such as VMS/CP/M/DOS, etc.) to mark file formats. In DOS terms, a file extension follows the file's main name, separated by a delimiter. In a file name like "example.txt", example is the file main name, txt is the file extension, indicating that the file is a plain text file, and the period "." is the separator between the file main name and the file extension.
DOS operating systems (including Windows 3.x) limit file extensions to 3 characters. Personal computers (PCs) have been on other Windows operating systems since Microsoft launched Windows 95, whether it is 16/32-bit Windows 95, Windows 98, Windows ME or 32-bit Windows NT, Windows 2000, Windows XP, Windows 2003 and Windows The FAT32 file system of Vista and Windows 7 contains an interface-level correction so that the number of characters in the file extension can reach 256 English characters (long file name), but at the system level, the 3-letter naming method is still retained. Invisible to many users. The NTFS file system does not have this limitation.
Common file extensions:
Instructions | Open\Edit mode | Chinese and foreign language full name | |
---|---|---|---|
ddb | Protel circuit schematic file | Design Explorer 99 SE opens the ||
Word document | Microsoft word and other software open the | DOCument | |
text document ( Plain text file) | Notepad, web browser and most other software. TeXT | ||
##Wps Text Editing System Documentation |
Jinshan The company's wps software opens WordProcessingSystem | xls | |
Excel spreadsheet |
Microsoft excel software opens | ||
Powerpoint presentation |
Open with Microsoft powerpoint and other software | ||
rar |
WinRAR Compressed file |
WinRAR, etc. open | |
##htm or html | Network page file (an application html under standard universal markup language) | Open in a web browser or web editor (such as W3C Amaya, FrontPage, etc.)HyperText Markup Language | |
Portable Document Format | Open with a pdf reader (such as Acrobat ), use pdf editor to editPortable Document Format | ||
dwg | CAD graphics file, (Extended Full name in Chinese: Figure) | Open software such as AutoCADDraWinG | |
exe | Executable files, executable applications | Windows operating systemEXEcutable | |
jpg | Common graphics files (Joint Photographic Expert Group) | Open with various graphics browsing software and graphics editorsJoint Photographic Expert Group | |
png | Portable network graphics, a transparent picture | Open with various graphics Browse software, graphics editorPortable Network Graphics | |
bmp | Bitmap file | Open with various graphics browsing software and graphics editorsBitMaP | |
Adobe FLASHVideo | Adobe FLASH Player or various audio and video playback software | ShockWave Flash | |
fla |
swf source file |
Adobe FLASH open |
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