Sometimes a subject of an e-mail message is prefixed with "Re: ."
What is this prefix? Is this a preposition? If so, why ":" is appended?
Thanks in advance.

Hi! Thanks for the question.

The prefix in "Re:" in the subject of email messages denote that the
message is in "reply" to a particular email either sent by you or
another person.

The original message meanwhile has the subject which contains the
words after the "Re:" prefix. So for example the email subject was

     Subject: Google Answers

When you or somebody replies to the email by clicking on the "reply"
button, which is present in most email programs or free email
services, the resulting form would be:

    Subject: Re: Google Answers

I found these resources which briefly discusses the things I mentioned
above.

"Re: Mail or Reply – To reply to a letter that you have received. This
action will automatically open a new mail message window, and place
the email address of the person who wrote the original message into
the To: field, and insert a phrase in the subject line (Re: subject
name of original letter.)"

"Email Basics"
http://etc.sccoe.k12.ca.us/i2000/00mod/i_usng/email/emailb.html

In this article about Microsoft Outlook, it mentions in the
"responding to a message" section it mentions that:

"Note the prefix RE: has been added denoting that this is a response
to an earlier message."

"Microsoft Outlook Basics"
http://www.fcds.org/faculty/CaroleTobias/Microsoft%20Outlook%20Basics.htm

Search terms used:  
"email basics" "re;" reply

I hope these links would help you in your research. Before rating this
answer, please ask for a clarification if you have a question or if
you would need further information.
 
Thanks for visiting us.  
 
Regards,  
Easterangel-ga  
Google Answers Researcher

---

Request for Answer Clarification by hhoriuchi-ga on 14 Jan 2003 02:54 PST

Thank you.

> The prefix in "Re:" in the subject of email messages denote that the
> message is in "reply" to

> "Note the prefix RE: has been added denoting that this is a response
> to an earlier message."

But when replying "Re: Google Answer", the subject of the reply becomes
"Re: Google Answer" not "Re: Re: Google Answer." Why?

---

Clarification of Answer by easterangel-ga on 14 Jan 2003 03:11 PST

Thanks for asking a clarification before making a rating. I have taken
note of your request and now looking for further information. Thank
you for your patience. :)

---

Clarification of Answer by easterangel-ga on 14 Jan 2003 03:37 PST

Hi again! I wasn't able to find anything concrete after doing some
searches but after consulting with my colleagues, these things are
usually based on the email software itself. In old versions of some
email software "re: Re:" was actually used in replies made to a
particular message.

In recent email clients "Re:" is not added anymore when it is already
present.

Thanks again!

---

Clarification of Answer by easterangel-ga on 14 Jan 2003 04:46 PST

In terms of the comments about having a prefix "re:" in the subject.
That is also true. In fact one could manually type "Re:" or in the
case of the clarification a "Re: Re:" on the subject line just as you
could type any letter, number or punctuation mark on that line. But
since we are talking about the intricacies of an email message which
includes the inner workings of a software, the "Re:" prefix is usually
known to be inserted whenever you pushed that "reply" button.

Thanks again!

Messages don't have to be replies in order to have the word Re: in
them.  Re is a preposition derived from Latin that means "in reference
to, in the case of, concerning."  Thus it is not uncommon to see a
memo between coleagues with subjects like "Re: Monday Meeting" even
though the message is not a reply to anything.
secret901-ga

Secret is correct. "Re" has nothing to do with the word "reply". It is
sometimes mistakenly taken for an abbreviation of "regarding". While
it does mean regarding or concerning, it is a word in its own right
(from the Latin "res"). See these links for more re "re".

http://www.askoxford.com/dictionary/re1
http://www.m-w.com/cgi-bin/dictionary

alex_p

You asked why a colon is used in conjunction with "re" if it is a
preposition (as it is). Grammatically it is the same as the following:

To: Jones, Smith, Rodriguez
From: Turner
Re: our last meeting
Date: January 14

Hope this helps.
alex_p

While the preposition “re” is certainly used to indicate the subject
of a memo, I do not agree with the inference that it keeps that
meaning when added by  the email software on the subject line, because
the original Latin word “res” means precisely “subject” (apart from
“thing”, “matter”, “substance”, and several other acceptions): it
would just be redundant. Then, in my opinion, when the email software
automatically ads “Re:” before the original line as we click on the
“reply” button, it is an abbreviation for “reply”.

Dear hhoriuchi-ga:
RE: your question (okay, pun mode off now.)

I agree fully with easterangel-ga's answer and reasoning. There is one
more instance in which you will see "Re: " at the start of  subject
line. And that's spam (un-solicited commercial email). It has become
popular to send a bulk email on, let's say get out of debt info. Since
almost everybody would automatically delete the email if the subject
was "get out of debt" the spammer would have the subject be something
like "Re: monday meeting" or "Re: Your Feedback Form". This is done in
the hopes of fooling people into opening the email instead of deleting
it.

sparky4ca-ga