BSD 2.11 - man page for from (bsd section 1)

FROM(1) 				       General Commands Manual					      FROM(1)

NAME
       from - who is my mail from?

SYNOPSIS
       from [ -s sender ] [ user ]

DESCRIPTION
       From  prints  out  the  mail  header lines in your mailbox file to show you who your mail is from.  If user is
       specified, then user's mailbox is examined instead of your own.	If the -s option is given, then only  headers
       for mail sent by sender are printed.

FILES
       /usr/spool/mail/*

SEE ALSO
       biff(1), mail(1)

4th Berkeley Distribution			    April 20, 1986					      FROM(1)