Compare contents of two files by deleting only unique lines from ‘file1′

comm -1 file1 file2

The command cmp is similar to diff:

# cmp file1 file2
file1 file2 differ: byte 10, line 1

If you use the diff command, you will be able to see the difference between the files as shown below:

diff file1 file2

diff -y file1 file2 -W 120 #View side by side