When you want to add a note or forgotten detail to a completed letter after signing off, you can include a postscript (PS). The prefix “post” means after, and is the opposite of “pre,” which means before. An example of a common addendum is, PS: I love you. Some people include a series of postscripts in their letters. The second postscript should be written with two P’s (PPS). This stands for post postscript. It is a common error to write PSS for the second postscript. Postscripts were more common before the digital age when letters were handwritten or typed. These days it is easy enough to insert a detail or comment within an email. Postscripts are rarely used in formal correspondence.