Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.

BUG:215923


git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdeedu@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da

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+<sect1 id="ai-timezones">
+<sect1info>
+<author>
+<firstname>Jason</firstname>
+<surname>Harris</surname>
+</author>
+</sect1info>
+<title>Time Zones</title>
+<indexterm><primary>Time Zones</primary>
+</indexterm>
+<para>
+The Earth is round, and it is always half-illuminated by the Sun.  However,
+because the Earth is spinning, the half that is illuminated is always changing.
+We experience this as the passing of days wherever we are on the Earth's
+surface.  At any given instant, there are places on the Earth passing from the
+dark half into the illuminated half (which is seen as <emphasis>dawn</emphasis>
+on the surface).  At the same instant, on the opposite side of the Earth, points
+are passing from the illuminated half into darkness (which is seen as
+<emphasis>dusk</emphasis> at those locations).  So, at any given time, different
+places on Earth are experiencing different parts of the day.  Thus, Solar time
+is defined locally, so that the clock time at any location describes the part of
+the day consistently.
+</para><para>
+This localization of time is accomplished by dividing the globe into 24 vertical
+slices called <firstterm>Time Zones</firstterm>.  The Local Time is the same
+within any given zone, but the time in each zone is one Hour
+<emphasis>earlier</emphasis> than the time in the neighboring Zone to the East.
+Actually, this is a idealized simplification; real Time Zone boundaries are not
+straight vertical lines, because they often follow national boundaries and other
+political considerations.
+</para><para>
+Note that because the Local Time always increases by an hour when moving between
+Zones to the East, by the time you move through all 24 Time Zones, you are a
+full day ahead of where you started.  We deal with this paradox by defining the
+<firstterm>International Date Line</firstterm>, which is a Time Zone boundary in
+the Pacific Ocean, between Asia and North America.  Points just to the East of
+this line are 24 hours behind the points just to the West of the line.  This
+leads to some interesting phenomena.  A direct flight from Australia to
+California arrives before it departs.  Also, the islands of Fiji straddle the
+International Date Line, so if you have a bad day on the West side of Fiji, you
+can go over to the East side of Fiji and have a chance to live the same day all
+over again.
+</para>
+</sect1>