At  02:11 PM 8/20/01 [my local time], Steve Dirickson wrote [in part]:
>Perhaps the first question to ask is "do I really need or want to see
>times displayed in the source's local time?" I submit that much, perhaps
>most, of the time the answer is "no". In the most common case, the users
>are all in the same time zone, so they all see the same time anyway. For a
>user halfway around the world from me, it is usually more useful for me to
>see times in my local reference point. For example, the message to which
>I'm replying was written last night at 22:49. Since I happen to know that
>the sender and I are both in the same time zone, I know that the message
>is about 14 hours old. However, if the source were in Central Europe, the
>message header would still say that the message was written at 22:49, and
>I would have to do the mental gymnastics to figure out that it was really
>only a few hours old. It would be much more useful for the message to show
>that it was written at 9:49 (or whatever it would be for Central Europe)
>this morning, my time.

My preferred email client, Eudora, has a configuration option (which I have
enabled) to automagically convert time references to my local timezone, so
I see the "natural" (from my personal time reference) normally.  If I read
the Date: header directly, I see the timestamp as included in the original
message (complete with UTC offset or timezone)... but the time in the email
title bar and in the mailbox summary listing is as of my local time.  For
example, in your posting's headers I see "Date: Mon, 20 Aug 2001 13:11:48
-0700" but in my window title bar and in the Eudora email summary listing
and in the automatically generated attribution in the first line of this
reply I see "02:11 PM" (since I'm in New Mexico and on Mountain Daylight
time).  I find it very convenient.  :)

On the topic of system versus local time, I think I basically agree with
the idea that timestamps should be stored in some standard universal form
(and UTC is a logical choice) and that users should (if needed) enter
and/or be shown times in their local format (including offset to their
timezone and any other format adjustments needed).  The questions of "what
day is it?" and "when did the day start?" and even "how long is that day?"
are complexities I've never seen answered well.  In my experience (small
companies generally) the people who needed to make the business decisions
about how "days" and "timezone" need to be handled didn't seem to grasp the
problem.  The whole notion of "today" is one of local perspective.  Monday
is almost over in New Zealand when Hawaii finally begins it.

Personally, I think it makes sense in an ever more globally connected world
to forego the whole notion of local timezone and daylight savings time.  We
should all just use UTC (or some equally global time system) and time
references at every level (from computer databases to what time the movie
starts) should be listed in that system.  On the other hand, what decade
was it that the US officially decided to adopt the metric system?  That
makes just as much sense... and we're still acting not only like it won't
ever happen but that it shouldn't.  Sad really, how social inertia limits
useful progress.  If only it were profitable to progress, it would already
be done.  As has been said somewhere (by Heinlein probably, though I don't
recall the reference [and it doesn't seem to be in the "Notebooks of
Lazarus Long"]) "Any question that begins with 'Why don't they...?' is
likely correctly answered 'Money.'"

-- Jeff

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