title: How to detemine the file type in Linux?
body: <p>If someone sends me a document (.pdf,.doc,.xls, ppt, .ogg, mp3, png, etc) without the extension, how can I determine the file type?  The /usr/bin/file command doesn't always guess right or it simply says that I have a Microsoft Office document.  I would like to know exactly so I can add the extension to the file name.</p>