How should be two files compared in UNIX system? 
                            Or
What is the use of ’cmp’ command in UNIX system?

‘cmp’ command is used to compare two file that they are identical or not. The two files are compared by byte and the location. If two files are  identical, cmp display no message, but simply  return the prompt.
Syntax:—
     <prompt> cmp file1 file2