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The kind of data stored in a file. Most modernoperating systems use the filename extension to determinethe file type though others store this information elsewherein the file system. The file type is used to choose anappropriate icon to represent the file in a GUI and thecorrect application with which to view, edit, run, or printthe file.Different operating systems support different sets of filetypes though most agree on a large common set and allowarbitrary new types to be defined.See also MIME.FileInfo.com - The File Extensions Resource(http://fileinfo.com/)