stream editor for filtering and transforming text

If no -e, --expression, -f, or --file option is given, then the first non-option argument is taken as the
sed script to interpret.  All remaining arguments are names  of  input  files;  if  no  input  files  are
specified, then the standard input is read.

-i[SUFFIX], --in-place[=SUFFIX]

       edit files in place (makes backup if extension supplied)