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

FROM(1) 										  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)