P.s. in mail

You're referring to a postscript (p.s.) in an email or letter!

A postscript is a note added at the end of a letter or email, usually indicated by the abbreviation "p.s." or "P.S.". It's a way to add a quick thought or afterthought that didn't fit in the main body of the message.

For example:

Dear [Name],

... (main message)

P.S. Don't forget to RSVP by Friday!

Best, [Your Name]

In this example, the postscript is a reminder to respond to the invitation by a certain date.