Syntax usage

-e Pass snippet of code

-n Loop over every line in a file, line in $_

-p Loop over every line in a file, line in $_, and adds a print after every line

-e followed by <file_name> process these files one at a time

-l Strip all \n and add back \n at the end of a printed line (-p)

-i Operate on file in-place (else you need to redirect to new file (> new_file) or it will go to console