No. They can tell you what software the file was created by, or to be used by. It will not tell you which computer it was made on.
They're used as extensions to identify picture files.
The file extension is the two, three, or more letter code that is after the period in a computer file name. It is used to "tell" the computer what type of file it is and what program on your computer will "open" or "run" it.
File extensions tell the computer what kind of program was used to create it, and are usually three letters. Common file extensions are .txt .doc .wps
Windows hides file extensions in File Explorer by default for known file types to simplify the user experience and reduce clutter. This setting can be adjusted in the Folder Options menu, where users can choose to show file extensions for all files. The option is typically turned on for security reasons, as displaying extensions can help users identify potentially harmful files. To view file extensions, users can enable the "File name extensions" checkbox in the "View" tab of the Ribbon in File Explorer.
For windows, you might use .cmd, .bat as common file extensions. Unix doesn't use file extensions as associations, so no file extension needs to be used in the Unix environment. A shell script in Unix is simply a text file with any name that is readable and executable. However, file extensions are typically used in Unix as a documentation aid that states that the file is a shell script. Common extensions are .sh, .csh, .ksh, .tcsh, .zsh, etc.
There are hundreds of filename extensions in use, and the set is constantly changing. The extensions are the characters after the period in dotted-name filename systems. They identify file types and serve to associate each with the application software that can properly interpret them. Please see the accompanying links for two Web sites that list file extensions.
Program file extensions simply identify the type of program. For example, an executable program will have a file extension of .exe, and some music files will have the file extension of .mp3
Computers use file extensions to determine a file's type.
Several video file extensions are used, which normally represent different file formats. Some of the commonly used extensions include AVI, MP4, MKV, but there are several others as well.
Right click the file and click properties or you can go into the folder settings and tick show file extensions which will show the full name in Windows Explorer
File extensions just tell your computer which program it needs to open the file. They also tell you what sort of file it is, for eg: If you got an email and there was an attachement called Sarah.jpg because of the .jpg at the end you know it is a photo file.
No, folders usually do not have file extensions, but they could have if you like. Usually only files have extensions, to indicate the contents of the file.