cmp
Linux Commands - Managing Files and Text

cmp

Compare two files.

cmp go go.c
go go.c differ: char1, line 1

The outcome above shows the place where these two files are different.
Here is another example showing where the two files do differ so you could verify that by looking at line 1.

cmp sp1.rtf sp.rtf
sp1.rtf sp.rtf differ: byte 1, line 1