Remove duplicate lines
Keep one copy of each line in your list.
Good to know
Which copy of a repeated line is kept?
The first occurrence stays in its original position. Later matching lines are removed.
Are different capitals treated as duplicates?
Use the ignore-case option to match lines such as Apple and apple. The first spelling is kept.
Why are two similar lines still present?
Spaces are part of the comparison. Trim unwanted spaces first if visually similar lines are not matching.