File name extensions are how OS X recognizes file types, and changing the extension is one way to associate a file with a different program. Sometimes, however, changing the file extension does not ...

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 ...

Red Eye Rose received a file with a strange extension. She doesn’t know into what program she should load it. Neither does Windows. I doubt that anyone knows all of the file extensions used since the ...

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 ...