Like most forms of communication, Email has certain seldom written
rules which, when followed, make life easier for everyone, but when
broken, can lead to misunderstanding and resentment. Following are
some guidelines to help you understand the issues involved in
sending email and to steer you clear of many common mistakes.
The most important thing to keep in mind is that email is always an imposition
on the recipient. Your job when sending a message is to make it as easy
as possible for your message to be read. Remember that not everyone is using
exactly the same computer with exactly the same programs as you are.
Your recipient may be using Windows, MacOS, or Unix, may be reading
their email on a desktop, palmtop, or cell phone, and they may have to
pay by the byte or by the minute to download their messages.
- Use Standard Formating
- If you are writing in English, then ALL of your email messages
should be sent as plain ASCII or UTF-8 text (not HTML,
Windows Text, MS-DOS Text, or ISO-anything text, just ASCII or UTF-8).
Remember that recipients who read their email on PDAs, cell-phones,
or pagers may not be able to read anything else. Those
reading their email over slow connections (such as dial-ups) will
also appreciate concise formatting.
Instructions for configuring most mail agents to use text.
If you must send a formatted document, be sure to use an OPEN STANDARD
format such as Rich Text Format (RTF) or Portable Document Format
(PDF). Formats like DOC, Word, DOS-TEXT, Excel, Power Point (pretty
much anything by Microsoft), some forms of TIFF, or anything with
"special" characters like accents or "smart quotes", are NOT
appropriate because they require the recipient to purchase your
particular version of proprietary software to read them. Even if you
know the recipient has similar software to yours, differences in
version or configuration can still make the attachment unreadable.
NEVER send a document in a non-standard format unless you KNOW that
ALL of your recipients are able to read and prefer that format.
- Avoid Large Messages
- Never send any message larger than about 10 kilobytes (or about
140 lines) unless the recipients have specifically requested it.
Even though that may not seem like much, remember that many people
use slow telephone modems or wireless connections to read their email.
People in Europe or using wireless devices often must pay by the
minute or the byte to receive your email. Most people also have limits
on the size of their mailbox. Sending a large file could fill up their
quota and prevent them from receiving any more mail!
- Never Send Executables
- NEVER EVER send an application (EXE) unless you KNOW EXACTLY what
it is and the person you are sending it to specifically requested it.
It could be a Trojan horse, contain a virus, or just plain crash their
machine. A program executable is the ultimate security breach and the ultimate
Likewise, you should NEVER open an executable email attachment unless
you not only know who sent it, but they have told you in advance
(preferably not by email) what to expect. Many "Trojan horses" rely
on forged headers to make you think a friend has sent you a program
such as a greeting card or a compressed file. If you get an
executable you weren't expecting, DELETE it immediately. Virus
protection software cannot help you if you run foreign attachments.
- Never Email Public Web Pages
- If something is on the web, even if it's small, email the URL instead.
This not only saves space, but it ensures that the page will be viewed
correctly, with all of it's images and links intact.
- Post Documents Instead of Mailing
- If you have a document that you wish to distribute to many people,
consider posting it on your own web page rather than emailing it. This
lets each person decide for themselves when and where they wish to view
the document and allows you to make changes and updates.
- Avoid Multimedia Content
- If you MUST send a picture or sound attachment via email use an open standard
format such as JPEG for photos,
GIF or PNG for icons and scanned text, AIFF for short sound glyphs, MP3 for music,
or MPEG for audio/video.
QuickTime is also a good catch-all because at least it is cross-platform and can be
- Ask Before Sending
- If you have a large document which you think people would be interested in
and you can't post it on the web, simply ASK first. Send a description of the
document and ask that people who are interested contact you. Be sure to
include in your description not just the content of the document, but its
format and what applications will be needed to view it.
- Suppress Long Recipient Lists
- If you are sending a message to a large number of people, have your mailer
suppress the recipients list. Those "
To:" lines can take up a
lot of space and some of your recipients may not appreciate having their email
addresses publicized to everyone else. Note that many viruses scan such
lists to find new victims.
If you can't figure out how to make your mailer suppress the send list,
listing the recipients in the "bcc" field will usually work. Test it first by
emailing yourself to make sure your mailer is working correctly.
- Suppress Excessive Headers
- Some internal mail systems, such as Lotus Notes, insert huge numbers of
non-standard headers into their emails. This not only wastes large amounts of
time and storage on material that most recipients can't read, but it also
breaks some email clients, preventing the messages from being read at all.
Either disable these features or use a standards compliant emailer when
sending to recipients outside your organization.
- Use Mailing Lists or Aliases When Needed
- If you want a large group of people to be able to exchange emails as a
group (a mailing list), ask your ISP or someone who administers a mail server
to set up a REAL list: don't just send a message to everyone and expect them
to reply-to-all. In addition to the problems with a long
recipient list, it is very unreliable and can result in confused and
fragmented conversation threads.
- Confirm Mailing List Subscriptions
- If you are maintaining a mailing list, do not assume that ANY subscription
request is genuine, especially if received via a web page. Your subscription
procedure should include sending a confirmation request to the newly
subscribed address. Mailing list messages should not be sent until
confirmation is received. If confirmation is not received within a certain
period of time, the request should be canceled.
- Avoid Automatic Reply To All
- When replying to a message, MAKE SURE that your mailer does not
automatically send your response to every recipient of the original
message unless you REALLY want it to. This is especially important
if there were a lot of recipients for the original message. Nothing
is more infuriating than someone doing a group reply to a 1000 person spam message
saying "Don't send me this stuff".
- Quote Appropriately
- When writing a reply, you should quote only the portion of the original
message which is directly relevant to your response: just enough to remind the
reader of what they were talking about. Taking a few seconds to delete
unnecessary quoted material will save a lot of space and make your message
much easier to read. NEVER quote an entire message just to say "Me Too!"
Also, configure your mailer to start each quoted line with some kind of
citation mark, such as "> ". This also makes reading your message
- Provide Appropriate Context
- Just as it is possible to have too much data in your replies, many
people put too little in their initial messages. Make sure that your
subject line provides a succinct description of what your message is
about. It should not exceed about fifty characters and it definitely
should not be a partial sentence that continues into the body of the
message. If the person you are writing to does not know you well,
start off with a one or two sentence introduction of yourself. Most
important of all, make sure your message begins by explaining what you
are talking about. This should repeat and expand upon the information
in your subject line. If you are writing about a web page, be sure to
include the URL. Remember that the person you are writing to may be
very busy maintaining many web presences, so it's important to tell
them up front what you are talking about.
- SPAM BAD
- NEVER send unsolicited email to large numbers of people (spam). It does
not matter if the content is commercial, political, religious, or humorous: it
is still spam. Many system administrators (myself included) treat spam as a
denial-of-service attack and will take action to have your account and/or your
ISP shutdown. Mail servers which send spam are routinely black-listed, so ISPs
have become very proactive in shutting down the accounts of spammers, even
But ISPs canceling your account might be the LEAST of your worries if you send
spam. Such attacks are federal felonies which the FBI is beginning to take
seriously. In some states, you can be fined up to $500 PER RECIPIENT for
sending unsolicited mass mailings. Just don't do it.
- Never Forward Chain Letters
- Any message which asks you to send copies to other people is a chain
letter. Chain letters are regarded almost as badly as spam and most ISPs will
cancel your account if you are caught doing this. The message may claim to be
in support of some worthy sounding cause, or it may claim to be spreading
important news. Just remember that you are responsible for anything you send
or pass on so research the issue carefully. See my page on Hoaxes for information on quickly identifying hoaxes.
See the CIAC Internet
Chain Letters page for some examples of recent chain letter hoaxes.
- Do Not Forge Headers
- Spammers often falsify their headers to make it difficult to track
the origins of their message. Certain types of denial of service
attacks also rely on falsified headers to cause unsuspecting
recipients to flood an innocent bystander's mailbox with angry replies
meant for the attacker. (NEVER reply to spam: even in the unlikely event
that your message reaches the actual sender, it will just invite more spam.)
Like spamming itself, forging headers is illegal in some states,
where this page is located. Even if your intent is just to perform
a joke, forged headers may still be illegal.
- And finally,
- Remember that not everyone is blessed with an infinite mailbox,
cable modem, and universal translators.
Seth B. Noble -
Email Etiquette -
sbnoble narda.net -
Updated February, 2005