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 ...

One of our readers reported that all the file extensions have changed to some unknown file format. If so, it could be a virus! If a virus has changed all the files extensions to unknown applications, ...

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 ...

When you double-click a file on your computer, Windows may launch an application to run or display the file. Windows knows how to do this because it maintains a list of known file types and the names ...

The type of file format that the current data will be saved to if no other file type is selected. For example, in a graphics program, the default file might be a JPEG or GIF. In Microsoft Word, the ...

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 ...

When you double-click on a file in Windows XP, the operating system will automatically open the file using a program that has been is associated with the file's extension. It is possible, though, to ...