How to Write An E-mail

I guess there are a lot of unspoken rules of netiquette which pertain to writing email. Perhaps it’s simply too much for many people to pick up in casual correspondence with their grandmother, but for those of us who use email regularly, our experience has lead to a set of guidelines for how emails should be formatted. My intention is to impart the most important of these rules to those who may not have yet discovered them.

These are not arbitrary whims of grumpy programmers, but rather the well-justified standards of professionals who have seen enough email to know what works and what does not. Complying with them will anger no one and can only gain you points in the tech world.


In the beginning was the word and the word was content-type: text/plain. (Johannes Tanzler), in comp.emacs.xemacs

Your email client / webmail service can likely send email in two different formats: ‘plain-text’ and ‘HTML’. The basic difference is that HTML can contain mark-up like hyperlinks, (inline) images, and bold text.

If you need to use those features, then use HTML format. Otherwise use plain-text.


  • Capability — people read their email in a lot of different fashions. Some read it on cell phones, some on PDAs. Some read it on the web, and some of us read it from old-school text-based terminals. Plain-text works on all of these. HTML fails miserably on many.
  • Size — HTML email takes up vastly more space. Add to that the fact that most email clients tack on a plain-text version of the email for an attempt at compatibility. This takes up even more space.
  • Spam — HTML is for spammers. Plain and simple. Realize that the vast majority of spammers use HTML-format because it allows them to include links and image ads. Spam filtering is generally done by employing algorithms which look for similarities between known spam and differences from known ham (non-spam email). Using HTML-format makes your message more likely to be incorrectly marked as spam and never delivered to the intended recipient.
  • Annoyingness — HTML empowers people to do a lot of annoying things to my display which I simply don’t want them to do. Nobody wants that wood-grain email background or handwritten-signature image. Let us read our text in peace.


Wrap your plain-text at 70-80 columns. Period. Long lines of text are irritating and hard to follow. Too short and the page will get needlessly long. 72 columns is the approximate accepted standard. This avoids being too long or too short, and includes enough space for a couple replies without making the email too wide. Your email client or editor should be able to do this for you. If it can’t, get a new one.

The Subject Line is Your Friend

For the love of Pete, enter a descriptive subject line. The subject line is like a first impression—make a good one or they may not bother to look closer. Some people get a lot of spam, and telling the recipient what you are actually writing about is the best way for them to identify which messages have contents they actually want.

The subject line is also the primary piece of information your recipient will have to identify the email if they come back to look for it later. If you think people don’t care, let me point out that I actually edit emails I receive to give them worthwhile subject lines.

Don’t put an entire email in the subject line. Just don’t do it. It’s weird. It’s especially bad if the subject line is too long to fit on the screen in one line of text. Some email readers do not wrap subject lines, and some provide no way to scroll horizontally to read the cut off portion.

Bad subject lines I have received include: “stuff”, “file”, “file2”, “haha”, “yeah…”, “Cam can please take care of this I think the mailbox is too big and we should empty it, ok?”.

Good subject lines I have received: “SG Halloween pics!”, “AFS costume contest prize”, “Facebook used as a weapon against students”, and “Advanced Operating Systems call number changed”.


Because it messes up the flow of reading.
> How come?
> > I prefer to reply inline.
> > > What do you do instead?
> > > > No.
> > > > > Do you like top-posting?

When replying, keeping a snippet of the original email in your message is a good way to remind your reader of the context of the reply. If you do this, however, put your response after the text it pertains to. Don’t respond to a question above the question. Lots of people do this. It’s annoying. Don’t do it.

Signature Lines

Including a signature line at the end of your email containing (at least) your name is generally a good practice to increase email readability. Your email client can probably include one automatically on your outgoing email.

If you do choose to use an email signature, you should offset it from the body of email with a line containing only -- (two dashes and a space). If you follow this convention, many email clients can recognize your signature for what it is and take appropriate action (such as highlighting it in a different color, or removing it in replies).

Don’t put anything other than text in your signature. Don’t attach a “vcard.” It may seem neat to you, but we don’t want it.


Don’t send .bmp files. Just don’t, they’re stupidly large. Convert it to a .jpeg or a .png.

And the final, most annoying habit that you should never, ever do: don’t place images inside .doc files before sending them! I see this all the time. Why do people do this?? Just send the images! Or put them in a .zip even! But don’t waste my space and make me open some slow word processing program I may not even have installed. And for what? If you figure it out, you tell me.