file

Determine file type. More information: https://manned.org/file.

• Give a description of the type of the specified file. Works fine for files with no file extension:
  file {{path/to/file}}
• Look inside a zipped file and determine the file type(s) inside:
  file -z {{foo.zip}}
• Allow file to work with special or device files:
  file -s {{path/to/file}}
• Don't stop at first file type match; keep going until the end of the file:
  file -k {{path/to/file}}
• Determine the MIME encoding type of a file:
  file -i {{path/to/file}}