Post script

"Post script" means:


 * 1) Aparagraph, phrase, etc., added to a letter that has already been concluded and signed by the writer.
 * 2) Any addition or supplement, as one appended by a writer to a book to supply further information.


 * Source: http://whatis.techtarget.com/definition/Postscript and http://www.dictionary.com/browse/postscript