Some file comes with no extension so we are unable to know what kind of application to associate with. Luckily Linux/Freebsd has a utility that can determine the file type.
file <the-file>
e.g.
$ file miami miami: JPEG image data, JFIF standard 1.02
$ file silly silly: Zip archive data, at least v1.0 to extract
$ file Read.Me Read.Me: ASCII text, with CRLF line terminators
See Ya !!!
