Sort lines of text files

Remove sections from each line of files

Display file contents

Report or omit repeated lines

text

duplicates

filtering

uniq

uniq filters out repeated lines in a file, often used after sort.

Remove duplicate lines

sort file.txt | uniq

Count occurrences

uniq -c file.txt

Show only duplicate lines

uniq -d file.txt

View file contents interactively

Output first part of files

Output last part of files