4 examples for uniq

  # This will show a count of all lines that have more than 1 copy. So only show the duplicates. (-d)
uniq -cd
        

  # Precede each line with number of occurrences
uniq -c
        

  # your_comment_here
uniq unique_file.data 
sort data_file | uniq
        

  # Count number of dublicates in file
uniq -C