A file extension, or file name extension, is the letters immediately shown after the last period in a file name. For example, the file extension.txt has an extension of .txt. This extension allows the ...

When you open files that have a particular file extension, Windows will look at its configuration to determine what the default program should be in order to work with these files. The default program ...

Microsoft uses file associations to set default programs for opening different file types on all its operating systems. As a result, when you open a file, be it text, image, or document, on your ...

A file extension is a suffix that is added to the end of a file name after a dot. It is usually two to four letters long. File extensions help Windows and other operating systems to know the standard ...

Mac OS X computers use a default application to open every file type based on its file extension. If you don't want to use the default application when opening a file, you can select "Open With" from ...

Back in the pre-Mac OS X and macOS days, Apple’s System 9 and earlier relied on hidden metadata to associate files with apps. File extensions, those bits of text that follow a period at the end of a ...