HTML and e-mail (was: Re: [LMB] Pictures to back up the idea of Jack Black as Miles)

[James Burbidge]

On 09/02/07, Katrina Knight <kknight at fastmail.fm> wrote:
> At 12:16 PM 2/9/2007 Peter H. Granzeau wrote:
> >You're not SPOSED to put HTML into e-mail, you know.  E-mail is
> >an ASCII-only service.
>
> E-mail is NOT an "ASCII-only" service. (This list, on the other
> hand, pretty much is.) HTML is quite common in e-mail, and is
> not against any of the standards for what e-mail can
> contain.  Whether that's a good thing or not depends on what you
> want. I don't want the HTML 95% of the times that it is used,
> but that doesn't mean it should never be used by anyone. Not
> using HTML when sending messages to plain text mailing lists is
> very much recommended though. The results of using HTML
> inappropriately vary from almost unreadable messages being sent
> out, to messages being rejected, to just aggravating people. I
> don't think anyone here wants any of those results. Use of HTML
> should be confined to situations where everyone involved agrees
> that it can be used. There are also assorted character sets that
> don't fit into what you'd call "ASCII-only". For some odd
> reason, people who don't use English want to be able to use the
> characters used by their own language in their messages. Again
> though, using other character sets is a problem with many
> mailing lists even though it is perfectly acceptable elsewhere.
>

Strictly speaking, HTML (being an ASCII-only markup format) is quite
compliant with the original SMTP (and other mail protocols, like UUCP)
protocol, but without the later MIME extensions marking it as a
variant type it may (probably won't) not display properly in a mail
client.  That is, you could mark up a "plain text" message as HTML and
send it, although the results wouldn't be what you expected: the
recipient would have to save the contents as a file with an
appropriate extension and then bring it up in a browser.  High-bit set
characters, though, are _not_ compliant with the original protocol
(which might use an "ascii" mode of transfer stripping off the high
bits), and would originally have had to be preserved with uuencode
(nowadays more likely a differnt MIME-encoding to seven-bit
characters).  Most mailers and gateways will now transmit eight-bit
characters, though, so the practical problem is just different display
variants for different character sets. (My recollection is that the
"old" list software stripped the high bits; and some listees also seem
to have mail readers which display only the stricly legal seven-bit
characters.)

James