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<title>Sources for time zone and daylight saving time data</title>
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- content="Sources for time zone and daylight saving time data">
-<meta name="DC.Creator" content="Eggert, Paul">
-<meta name="DC.Contributor" content="Olson, Arthur David">
-<meta name="DC.Date" content="2017-02-28">
-<meta name="DC.Description"
- content="Sources of information about time zones and daylight saving time">
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- content="https://www.iana.org/time-zones/repository/tz-link.htm">
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- content="database,daylight saving,DST,time zone,timezone,tz,zoneinfo">
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<body>
<h1>Sources for time zone and daylight saving time data</h1>
<abbr title="Operating System">OS</abbr></a>,
<a href="https://www.freebsd.org">Free<abbr
title="Berkeley Software Distribution">BSD</abbr></a>,
-<a href="http://netbsd.org">Net<abbr>BSD</abbr></a>,
-<a href="http://www.openbsd.org">Open<abbr>BSD</abbr></a>,
-<a href="http://www.chromium.org/chromium-os">Chromium OS</a>,
+<a href="http
s://netbsd.org">Net<abbr>BSD</abbr></a>,
+<a href="http
s://www.openbsd.org">Open<abbr>BSD</abbr></a>,
+<a href="https://www.chromium.org/chromium-os">Chromium OS</a>,
<a href="https://cygwin.com">Cygwin</a>,
<a href="http://www.delorie.com/djgpp/"><abbr
title="DJ's GNU Programming Platform">DJGPP</abbr></a>,
<a href="https://en.wikipedia.org/wiki/MINIX">MINIX</a>,
+<a href="https://www.mysql.com">MySQL</a>,
<a href="https://en.wikipedia.org/wiki/WebOS"><abbr
title="Web Operating System">webOS</abbr></a>,
-<a href="http://ibm.com/aix"><abbr
+<a href="http
s://ibm.com/aix"><abbr
title="Advanced Interactive eXecutive">AIX</abbr></a>,
<a href="https://en.wikipedia.org/wiki/BlackBerry_10">BlackBerry 10</a>,
-<a href="http://www.apple.com/ios/"><abbr
+<a href="http
s://www.apple.com/ios/"><abbr
title="iPhone OS">iOS</abbr></a>,
-<a href="http://www.apple.com/macos/">macOS</a>,
+<a href="https://www.apple.com/macos/">macOS</a>,
<a href="https://www.microsoft.com/en-us/windows">Microsoft Windows</a>,
<a href="https://www.hpe.com/info/openvms">Open<abbr
title="Virtual Memory System">VMS</abbr></a>,
The database also records when daylight saving time was in use,
along with some time zone abbreviations such as <abbr>EST</abbr>
for Eastern Standard Time in the <abbr>US</abbr>.</p>
+<h2 id="download">Downloading the <code><abbr>tz</abbr></code> database</h2>
<p>
The following <a
href="https://en.wikipedia.org/wiki/Unix_shell">shell</a> commands download
<p>
The <code><abbr>tz</abbr></code> code and data
are by no means authoritative. If you find errors, please
-send changes to the <a href="mailto:tz@iana.org">time zone
-
mailing list</a>. You can also <a
+send changes to <a href="mailto:tz@iana.org"><code>tz@iana.org</code></a>,
+
the time zone mailing list. You can also <a
href="https://mm.icann.org/mailman/listinfo/tz">subscribe</a> to it
and browse the <a
href="https://mm.icann.org/pipermail/tz/">archive of old
messages</a>.</p>
<p>
If your government plans to change its time zone boundaries or
-daylight saving rules, let the mailing list know well in advance. With
+daylight saving rules, inform <code>tz@iana.org</code> well in
+advance, as this will coordinate updates to many cell phones,
+computers, and other devices around the world. With
less than a year's notice there is a good chance that some
computer-based clocks will operate incorrectly after the change, due
to delays in propagating updates to software and data. The shorter
-the notice, the more likely clock problems will arise.
+the notice, the more likely clock problems will arise; see "<a
+href="https://codeofmatt.com/2016/04/23/on-the-timing-of-time-zone-changes/">On
+the Timing of Time Zone Changes</a>" for examples.
+</p>
+<p>
+Changes to the <code><abbr>tz</abbr></code> code and data are often
+propagated to clients via operating system updates, so
+client <code><abbr>tz</abbr></code> data can often be corrected by
+applying these updates. With GNU/Linux and similar systems, if your
+maintenance provider has not yet adopted the
+latest <code><abbr>tz</abbr></code> data, you can often short-circuit
+the process by tailoring the generic instructions in
+the <code><abbr>tz</abbr> README</code> file and installing the latest
+data yourself. System-specific instructions for installing the
+latest <code><abbr>tz</abbr></code> data have also been published
+for <a href="https://www.ibm.com/developerworks/aix/library/au-aix-olson-time-zone/index.html"><abbr>AIX</abbr></a>,
+<a
+href="http://userguide.icu-project.org/datetime/timezone"><abbr
+title="International Components for Unicode">ICU</abbr></a>,
+<a href="https://developer.ibm.com/javasdk/support/dst/jtzu/"><abbr>IBM</abbr></a>
+and <a
+href="http://www.oracle.com/technetwork/java/javase/tzupdater-readme-136440.html">Oracle</a>
+Java, <a href="http://www.joda.org/joda-time/tz_update.html">Joda-Time</a>, <a
+href="https://dev.mysql.com/doc/refman/en/time-zone-support.html">MySQL</a>,
+and <a
+href="http://nodatime.org/userguide/tzdb">Noda Time</a> (see below).
</p>
<p>Sources for the <code><abbr>tz</abbr></code> database are
<a href="https://en.wikipedia.org/wiki/UTF-8"><abbr
which can be modified by common text editors such
as <a href="https://www.gnu.org/software/emacs/">GNU Emacs</a>,
<a href="https://wiki.gnome.org/Apps/Gedit">gedit</a>, and
-<a href="http://www.vim.org">vim</a>. One
-editor has a package to simplify editing further:</p>
-<ul>
-<li><a href="https://packagecontrol.io/packages/zoneinfo">Sublime
-zoneinfo</a> is a <a href="http://www.sublimetext.com">Sublime
-Text</a> package for syntax highlighting <code><abbr>tz</abbr></code>
-source files.</li>
-</ul>
+<a href="http://www.vim.org">vim</a>.
+Specialized source-file editing can be done via the
+<a href="https://packagecontrol.io/packages/zoneinfo">Sublime
+zoneinfo</a> package for <a
+href="https://www.sublimetext.com">Sublime Text</a> and the <a
+href="https://marketplace.visualstudio.com/items?itemName=gilmoreorless.vscode-zoneinfo">VSCode
+zoneinfo</a> extension for <a href="https://code.visualstudio.com">Visual
+Studio Code</a>.
+</p>
<p>
For further information about updates, please see
<a href="https://tools.ietf.org/html/rfc6557">Procedures for
Maintaining the Time Zone Database</a> (Internet <abbr
-title="Request For Comments">RFC</abbr> 6557).</p>
+title="Request For Comments">RFC</abbr> 6557). More detail can be
+found in <a href="theory.html">Theory and pragmatics of the tz code and data</a>.
+</p>
<h2 id="commentary">Commentary on the <code><abbr>tz</abbr></code> database</h2>
<ul>
<li>The article
tz Database Source Files</a> explains the <code><abbr>tz</abbr></code>
database format.</li>
<li><a
-href="http://codeofmatt.com/2016/04/23/on-the-timing-of-time-zone-changes/">On
-the Timing of Time Zone Changes</a> gives examples of problems caused
-by inadequate notice by governments of time zone and daylight saving
-rule changes.</li>
-<li><a
href="https://blog.jonudell.net/2009/10/23/a-literary-appreciation-of-the-olsonzoneinfotz-database/">A
literary appreciation of the Olson/Zoneinfo/tz database</a> comments on the
database's style.</li>
These are listed roughly in ascending order of complexity and fanciness.
</p>
<ul>
-<li><a href="http://time.is">Time.is</a> shows locations'
+<li><a href="https://time.is">Time.is</a> shows locations'
time and zones in a simple format.</li>
<li><a href="https://www.timejones.com">TimeJones.com</a> is a simple
time zone converter.</li>
uses a pulldown menu.</li>
<li><a href="http://home.kpn.nl/vanadovv/time/TZworld.html">Complete
timezone information for all countries</a> displays tables of DST rules.
-<li><a href="http://www.timeanddate.com/worldclock/">The World Clock –
+<li><a href="https://www.timeanddate.com/worldclock/">The World Clock –
Worldwide</a> lets you sort zone names and convert times.</li>
<li><a href="http://www.zeitverschiebung.net/en/">Time Difference</a>
calculates the current time difference between locations.</li>
(Internet <abbr>RFC</abbr> 7808), a time zone data distribution service,
along with <a href="https://tools.ietf.org/html/rfc7809">CalDAV</a>
(Internet <abbr>RFC</abbr> 7809), a calendar access protocol for
-transferring time zone data by reference. The draft <a name="TZDIST-Geolocate"
+transferring time zone data by reference. The (expired) draft <a
+id="TZDIST-Geolocate"
href="https://tools.ietf.org/html/draft-murchison-tzdist-geolocate-00">TZDIST
-Geolocate Extension</a> lets a client determine its time zone region
+Geolocate Extension</a> would have let a client determine its time zone region
from its geographic location using a <a
href="https://tools.ietf.org/html/rfc5870">'geo' URI</a>.</li>
<li>The <a href="https://tools.ietf.org/html/rfc5545">
Database Parser</a> is a
<a href="https://en.wikipedia.org/wiki/C%2B%2B">C++</a> parser and
runtime library. It is freely available under the
-<a href="http://creativecommons.org/licenses/by/4.0/">Creative Commons
+<a href="https://creativecommons.org/licenses/by/4.0/">Creative Commons
Attribution 4.0 International Public License</a>.</li>
-<li><a name="ICU" href="http://site.icu-project.org">International Components for
+<li><a id="ICU" href="http://site.icu-project.org">International Components for
Unicode (<abbr>ICU</abbr>)</a> contains C/C++ and <a
href="https://en.wikipedia.org/wiki/Java_%28programming_language%29">Java</a>
libraries for internationalization that
<abbr>ICU</abbr> is freely available under a
<abbr>BSD</abbr>-style license.</li>
<li>The <a href="https://github.com/lau/tzdata">Tzdata</a> package for
-the <a href="http://elixir-lang.org">Elixir</a> language downloads
+the <a href="https://elixir-lang.org">Elixir</a> language downloads
and compiles tz source and exposes <abbr
title="Application Program Interface">API</abbr>s for use. It is
freely available under the <abbr
<code><abbr>tz</abbr></code> source into a binary format. It inspired
Java 8 <code>java.time</code>, which its users should migrate to once
they can assume Java 8 or later. It is available under the <a
-href="http://www.apache.org/licenses/LICENSE-2.0">Apache License</a>.</li>
+href="https://www.apache.org/licenses/LICENSE-2.0">Apache License</a>.</li>
<li><a href="https://github.com/MenoData/Time4J/">Time4J –
Advanced date, time and interval library for Java</a> contains a class
<code>net.time4j.tool.TimezoneRepositoryCompiler</code> that compiles
<li><a href="https://en.wikipedia.org/wiki/JavaScript">JavaScript</a>-based
compilers and libraries include:
<ul>
-<li><a href="http://momentjs.com/timezone/">Moment Timezone</a> is a
-plugin for the <a href="http://momentjs.com">Moment.js</a> date
+<li><a href="https://momentjs.com/timezone/">Moment Timezone</a> is a
+plugin for the <a href="https://momentjs.com">Moment.js</a> date
manipulation library. It is freely available under the <abbr>MIT</abbr>
license.</li>
<li><a href="https://github.com/mde/timezone-js">TimezoneJS.Date</a>'s
</ul>
<li><a href="https://github.com/JuliaTime/">JuliaTime</a> contains a
compiler from <code><abbr>tz</abbr></code> source into
-<a href="http://julialang.org/">Julia</a>. It is freely available
+<a href="https://julialang.org/">Julia</a>. It is freely available
under the <abbr>MIT</abbr> license.</li>
<li><a href="http://pytz.sourceforge.net">pytz – World Timezone
Definitions for Python</a> compiles <code><abbr>tz</abbr></code> source into
<a href="https://www.python.org">Python</a>.
It is freely available under a <abbr>BSD</abbr>-style license.</li>
-<li><a href="http://tzinfo.github.io">TZInfo –
+<li><a href="https://tzinfo.github.io">TZInfo –
Ruby Timezone Library</a>
compiles <code><abbr>tz</abbr></code> source into
<a href="https://www.ruby-lang.org/en/">Ruby</a>.
zone repository whose format
is either proprietary or an <abbr>XML</abbr>-encoded
representation.</li>
-<li><a name="Tcl" href="http://tcl.tk">Tcl</a>
+<li><a id="Tcl" href="https://tcl.tk">Tcl</a>
contains a developer-oriented parser that compiles <code><abbr>tz</abbr></code>
source into text files, along with a runtime that can read those
files. Tcl is freely available under a <abbr>BSD</abbr>-style
in its JavaScript library for time zone conversion. Dates before 1970
are not supported.</li>
<li>The <a
-href="http://hackage.haskell.org/package/timezone-olson">timezone-olson</a>
+href="https://hackage.haskell.org/package/timezone-olson">timezone-olson</a>
package contains <a href="https://www.haskell.org">Haskell</a> code that
parses and uses <code><abbr>tz</abbr></code> binary data. It is freely
available under a <abbr>BSD</abbr>-style license.</li>
<a href="https://en.wikipedia.org/wiki/Windows_Runtime">Windows Runtime</a>
classes such as <a
href="https://msdn.microsoft.com/en-us/library/windows/apps/windows.globalization.datetimeformatting.datetimeformatter.aspx"><code>DateTimeFormatter</code></a>.
-<a name="System.TimeZoneInfo"
+<a id="System.TimeZoneInfo"
href="https://blogs.msdn.microsoft.com/bclteam/2007/06/07/exploring-windows-time-zones-with-system-timezoneinfo-josh-free/">Exploring
Windows Time Zones with <code>System.TimeZoneInfo</code></a> describes
the older, proprietary method of Microsoft Windows 2000 and later,
which stores time zone data in the
<a href="https://en.wikipedia.org/wiki/Windows_Registry">Windows Registry</a>. The
<a
-href="http://www.unicode.org/cldr/charts/latest/supplemental/zone_tzid.html">Zone →
+href="http://unicode.org/cldr/charts/latest/supplemental/zone_tzid.html">Zone →
Tzid table</a> or <a
-href="http://unicode.org/repos/cldr/trunk/common/supplemental/windowsZones.xml"><abbr>XML</abbr>
+href="http
s://unicode.org/repos/cldr/trunk/common/supplemental/windowsZones.xml"><abbr>XML</abbr>
file</a> of the <abbr>CLDR</abbr> data maps proprietary zone IDs
to <code><abbr>tz</abbr></code> names.
<li><a
Java</a> contains a copy of a subset of a recent
<code><abbr>tz</abbr></code> database in a
Java-specific format.</li>
-<li><a href="https://kimmo.suominen.com/sw/timezone/">Time Zone</a> is
-a <a href="https://wordpress.org">WordPress</a> plugin. It is freely
-available under a <abbr>BSD</abbr>-style license.</li>
<li><a href="http://www.relativedata.com/time-zone-master">Time Zone
Master</a> is a Microsoft Windows clock program that can automatically
download, compile and use <code>tz</code> releases. The Basic version
</ul>
<h2 id="other-dbs">Other time zone databases</h2>
<ul>
-<li><a href="http://www.astro.com/atlas">Time-zone Atlas</a>
+<li><a href="https://www.astro.com/atlas">Time-zone Atlas</a>
is Astrodienst's Web version of Shanks and Pottenger's
time zone history atlases also published in <a
href="http://astrocom.com/astrology-products/software/acs-atlas-software">software</a>
contains data from the Time Service Department of the
<abbr>US</abbr> Naval Observatory.</li>
<li>The <a
-href="http://www.iata.org/publications/store/Pages/standard-schedules-information.aspx">Standard
+href="https://www.iata.org/publications/store/Pages/standard-schedules-information.aspx">Standard
Schedules Information Manual</a> of the
International Air Transport Association
gives current time zone rules for airports served by commercial aviation.</li>
href="https://www.cia.gov/library/publications/the-world-factbook/graphics/ref_maps/physical/pdf/standard_time_zones_of_the_world.pdf">time
zone map</a>; the
<a
-href="http://www.lib.utexas.edu/maps/world.html">Perry–Castañeda
+href="https://www.lib.utexas.edu/maps/world.html">Perry–Castañeda
Library Map Collection</a>
of the University of Texas at Austin has copies of
recent editions.
<ul>
<li><a href="https://github.com/evansiroky/timezone-boundary-builder">Timezone
Boundary Builder</a> extracts
-<a href="http://www.openstreetmap.org">Open Street Map</a> data to build
+<a href="https://www.openstreetmap.org">Open Street Map</a> data to build
boundaries of <code><abbr>tz</abbr></code> regions.
Its code is freely available under the <abbr>MIT</abbr> license, and
its data entries are freely available under the
-<a href="http://opendatacommons.org/licenses/odbl/">Open Data Commons
+<a href="https://opendatacommons.org/licenses/odbl/">Open Data Commons
Open Database License</a>. The maps' borders appear to be quite accurate.</li>
<li><a href="http://efele.net/maps/tz/"><abbr>TZ</abbr> timezones
maps</a> contains <a
href="https://en.wikipedia.org/wiki/Shapefile">shapefiles</a> of
sets of <code><abbr>tz</abbr></code> regions. This includes
<a href="http://efele.net/maps/tz/world/">tz_world</a>, a shapefile
-for all the world's regions</li>
+for all the world's regions. These maps are no longer maintained and
+are superseded by the Timezone Boundary Builder.</li>
<li><a
href="https://github.com/straup/whereonearth-timezone">Whereonearth-timezone</a>
is in <a href="https://tools.ietf.org/html/rfc7946">GeoJSON</a> format
Commercial network API access is provided
by <a href="https://askgeo.com">AskGeo</a>
and <a href="https://www.geogarage.com/blog/news-1/post/geogarage-time-zone-api-31">GeoGarage</a>.
-Also, an <a
-href="https://mm.icann.org/pipermail/tz/2016-October/024309.html">experimental
-server</a> is available for the TZDIST Geolocate Extension mentioned
-<a href="#TZDIST-Geolocate">above</a>.</li>
+</li>
<li>"<a
-href="http://stackoverflow.com/questions/16086962/how-to-get-a-time-zone-from-a-location-using-latitude-and-longitude-coordinates/16086964">How
+href="https://stackoverflow.com/questions/16086962/how-to-get-a-time-zone-from-a-location-using-latitude-and-longitude-coordinates/16086964">How
to get a time zone from a location using latitude and longitude
coordinates?</a>" discusses other geolocation possibilities.</li>
<li><a href="http://statoids.com/statoids.html">Administrative
zone boundaries for multizone countries</a> summarizes legal
boundaries between time zones within countries.</li>
<li>Manifold.net's <a
-href="http://manifold.net/info/freestuff.shtml">Free Stuff for
+href="http://manifold.net/info/freestuff.shtml">Free Downloads for
Manifold System Users</a> includes a Manifold-format map of
world time zone boundaries distributed under the
<abbr>GPL</abbr>.</li>
-<li>The GeoCommunity lists several commercial sources for <a
-href="http://spatialnews.geocomm.com/features/timezones/">International
-Time Zones and Time Zone Data</a>.</li>
<li>A ship within the <a
href="https://en.wikipedia.org/wiki/Territorial_waters">territorial
waters</a> of any nation uses that nation's time. In international
</ul>
<h2 id="civil">Civil time concepts and history</h2>
<ul>
-<li><a href="http://physics.nist.gov/time">A
+<li><a href="https://www.nist.gov/pml/time-and-frequency-division/popular-links/walk-through-time">A
Walk through Time</a>
surveys the evolution of timekeeping.</li>
<li><a href="http://www.webexhibits.org/daylightsaving/">About Daylight
<li><a href="http://seizethedaylight.com/dst/">A Brief
History of Daylight Saving Time</a> summarizes some of the contentious
history of <abbr>DST</abbr>.</li>
-<li><a href="http://www.staff.science.uu.nl/~gent0113/idl/idl.htm">A History of
+<li><a href="https://www.staff.science.uu.nl/~gent0113/idl/idl.htm">A History of
the International Date Line</a> tells the story of the most important
time zone boundary.</li>
<li><a href="http://statoids.com/tconcept.html">Basic Time
<dl>
<dt>Australia</dt>
<dd>The Parliamentary Library has commissioned a <a
-href="http://www.aph.gov.au/binaries/library/pubs/rp/2009-10/10rp10.pdf">research
+href="https://www.aph.gov.au/binaries/library/pubs/rp/2009-10/10rp10.pdf">research
paper on daylight saving time in Australia</a>.
The Bureau of Meteorology publishes a list of <a
href="http://www.bom.gov.au/climate/averages/tables/dst_times.shtml">Implementation
<dt>Canada</dt>
<dd>National Research Council Canada publishes current
and some older information about <a
-href="http://www.nrc-cnrc.gc.ca/eng/services/time/time_zones.html">time
+href="https://www.nrc-cnrc.gc.ca/eng/services/time/time_zones.html">time
zones & daylight saving time</a>.</dd>
<dt>Chile</dt>
<dd>The Hydrographic and Oceanographic Service of the Chilean Navy publishes a
Chile's official time (in Spanish)</a>.</dd>
<dt>Germany</dt>
<dd>The National Institute for Science and Technology maintains the <a
-href="http://www.ptb.de/cms/en/fachabteilungen/abt4/fb-44/ag-441/realisation-of-legal-time-in-germany.html">Realisation
+href="https://www.ptb.de/cms/en/fachabteilungen/abt4/fb-44/ag-441/realisation-of-legal-time-in-germany.html">Realisation
of Legal Time in Germany</a>.</dd>
<dt>Israel</dt>
<dd>The Interior Ministry periodically issues <a
hreflang="he">announcements (in Hebrew)</a>.</dd>
<dt>Italy</dt>
<dd>The National Institute of Metrological Research maintains a
-<a href="http://www.inrim.it/res/tf/ora_legale_i.shtml">table of civil time
+<a href="http://www.nanospin.eu/res/tf/ora_legale_i.shtml">table of civil time
(in Italian)</a>.</dd>
<dt>Mexico</dt>
<dd>The Investigation and Analysis Service of the Mexican Library of
<dt>Malaysia</dt>
<dd>See Singapore <a href="#Singapore">below</a>.</dd>
<dt>Netherlands</dt>
-<dd><a href="http://www.staff.science.uu.nl/~gent0113/wettijd/wettijd.htm"
+<dd><a href="https://www.staff.science.uu.nl/~gent0113/wettijd/wettijd.htm"
hreflang="nl">Legal time in the Netherlands (in Dutch)</a>
covers the history of local time in the Netherlands from ancient times.</dd>
<dt>New Zealand</dt>
href="http://astrologyschool.com/nztime.html">History of New Zealand
time</a> has more details.</dd>
<dt>Singapore</dt>
-<dd><a name="Singapore"
+<dd><a id="Singapore"
href="http://www.math.nus.edu.sg/aslaksen/teaching/timezone.html">Why
is Singapore in the "Wrong" Time Zone?</a> details the
history of legal time in Singapore and Malaysia.</dd>
<h2 id="precision">Precision timekeeping</h2>
<ul>
<li><a
-href="http://literature.agilent.com/litweb/pdf/5965-7984E.pdf">The
+href="http://leapsecond.com/hpan/an1289.pdf">The
Science of Timekeeping</a> is a thorough introduction
to the theory and practice of precision timekeeping.</li>
<li><a href="http://www.ntp.org"><abbr
<li>The <a
href="https://pairlist6.pair.net/mailman/listinfo/leapsecs">Leap
Second Discussion List</a> covers <a
-href="http://www2.unb.ca/gge/Resources/gpsworld.november99.pdf">McCarthy
+href="https://www2.unb.ca/gge/Resources/gpsworld.november99.pdf">McCarthy
and Klepczynski's 1999 proposal to discontinue leap seconds</a>,
discussed further in
-<a href="http://www.cl.cam.ac.uk/~mgk25/time/metrologia-leapsecond.pdf">The
+<a href="https://www.cl.cam.ac.uk/~mgk25/time/metrologia-leapsecond.pdf">The
leap second: its history and possible future</a>.
<a href="http://www.ucolick.org/~sla/leapsecs/"><abbr>UTC</abbr>
might be redefined
</ul>
<h2 id="notation">Time notation</h2>
<ul>
-<li>The <a name="CLDR" href="http://cldr.unicode.org">Unicode Common Locale Data
+<li>The <a id="CLDR" href="http://cldr.unicode.org">Unicode Common Locale Data
Repository (<abbr>CLDR</abbr>) Project</a> has localizations for time
zone names, abbreviations, identifiers, and formats. For example, it
contains French translations for "Eastern European Summer Time",
"<abbr title="Eastern European Summer Time">EEST</abbr>", and
"Bucharest". Its
-<a href="http://www.unicode.org/cldr/charts/latest/by_type/">by-type
+<a href="http://unicode.org/cldr/charts/latest/by_type/">by-type
charts</a> show these values for many locales. Data values are available in
both <abbr title="Locale Data Markup Language">LDML</abbr>
(an <abbr>XML</abbr> format) and <abbr>JSON</abbr>.
<li>
-<a href="http://www.cl.cam.ac.uk/~mgk25/iso-time.html">A summary of
+<a href="https://www.cl.cam.ac.uk/~mgk25/iso-time.html">A summary of
the international standard date and time notation</a> is a good
summary of
<a
<a href="https://www.hackcraft.net/web/datetime/">Date & Time
Formats on the Web</a> surveys web- and Internet-oriented date and time
formats.</li>
-<li>
-<a href="http://exit109.com/~ghealton/y2k/yrexamples.html">The
-Best of Dates, the Worst of Dates</a> covers many problems encountered
-by software developers when handling dates and time stamps.</li>
<li>Alphabetic time zone abbreviations should not be used as unique
identifiers for <abbr>UTC</abbr> offsets as they are ambiguous in
practice. For example, in English-speaking North America
</ul>
<h2 id="see-also">See also</h2>
<ul>
+<li><a href="theory.html">Theory and pragmatics of the tz code and data</a></li>
<li><a href="tz-art.htm">Time and the Arts</a></li>
</ul>
<hr>
projects / platform / upstream / tzdata.git / blobdiff