Date and Time

Non-technical and technical date and time links.

1. Current Time

2. Standards

2.1 Standard Organizations & Standards

2.2 Unusual Standards

2.3 ISO 8601 Commentary Links

2.4 Comments on other standards

3. Organizations, Timekeeping

4. Non-Technical

4.1 General

4.2 GPS

4.3 Daylight Savings Time (a.k.a., Summer Time)

4.4 Leap Seconds

4.5 Miscellaneous

4.6 Odd Stuff

4.7 Historic Information

4.8 Millennium Change

4.9 Time Zones and International Dateline

5. Technical

5.1 Computer Science Links

5.1.1 General

5.1.2 Macintosh

5.1.3 Microsoft Windows®

5.1.4 Internet

5.1.5 C

5.1.6 Perl

5.1.7 UNIX

5.2 Daylight Savings Time (a.k.a., Summer Time)

5.3 General

5.4 GPS

5.5 Organizations

6. Year 2000 Links

6.1 Computer Science

6.2 Other

7. Year 2038 Links

Hits since 2002-01-21:

• 1. Current Time

  USNO  UTC

  Where to go for a "really good time".
  NOTE: NTP or NTS provide the best time synchronization for your computer. See NIST for basic free software for popular computers. Serious networkers will likely prefer NTP.
   
• Bureau International des Poids et Mesures
  (International Bureau of Weights and Measures)
  (more BIPM links elsewhere)
• NIST: National Institute of Standards and Technology
  (more NIST links elsewhere on this page)
  • The Official Time Of The U.S.A. [2001-12]
    Time and Frequency Division.
    (With and without Java Applet: select "DISABLE JAVA ANIMATION" to disable Java)
  • Network Time Service (NTS) Support [2002-01]
    Download programs to sync your computer with NIST (accurate way to set your computer's time... for dial-up users, turn OFF "periodic queries" to manually query once a day).
    Ideal for most Microsoft Windows and Macintosh systems.
    Also see NTP below for serious servers.
• USNO: United States Naval Observatory [2002-01]
  (more USNO links elsewhere on this page)
  • U.S. Naval Observatory Master Clock time [2002-01]
    UTC and all USA time zones as static "pure text" page
  • Animated GIF clocks (sadly, only for Netscape browsers) [2002-01]
• WorldTime: interactive atlas, time info, public holidays [2001-11]
  • Current time, stars, world view, ... [2002-01]
  
   

• 2. Standards

  • 2.1 Standard Organizations & Standards

  • BIPM: Bureau International des Poids et Mesures [2002-01]
    International Bureau of Weights and Measures
    The task of the BIPM is to ensure world-wide uniformity of measurements and their traceability to the International System of Units (SI).
    • Glossary [2002-01]
      9TF.686 Referenced by ISO 8601 standard in 3.1
      (pay for download)
  • European Committee For Standardization. [2002-01]
    "Owner" of EN 28601 (but good luck in finding the page where they state they own it! Member nations actually sell it.)
  • UNECE: United Nations Economic Commission for Europe [2002-01]
     

  • 2.2 Unusual Standards

    
     

  • 2.3 ISO 8601 Commentary Links

    Provides additional info on ISO 8601
    (also see previous Standard Organizations for ISO itself and following Technical Computer Science links)
     
  • Commercial Sites Selling Official Copies of the ISO 8601 standard.
    All national standards organizations participating with ISO are required to ensure copies of the standards are available within their own country. Check your local standard organization for details.
    • ISO Store [2002-01]
      • ISO 8601:2000 document [2002-01]
    • American National Standards Institute [2002-01]
      (start here if the following link changes)
    • Global Engineering Documents [2002-01]
      For hard-copy standards
  • Unofficial draft copies of ISO 8601 Standard (official copies require purchase)
    (I would be interested in adding more links to with sites containing numerous links to known copies)
    • Download a Draft Copy of the ISO 8601 Date and Time Standard as a PDF file [2006-02]
      Links to many download site s, ftom the latest to the oldest standard.
  • Unofficial draft copies of ISO 8601 Standard (official copies require purchase)
    (I would be interested in adding more links to with sites containing numerous links to known copies)
  • The Best Of Dates, The Worst Of Dates [2002-01]
    Includes a detailed description of ISO 8601
  • Date and Time Formats [2002-01]
    Some tips and links. Including various standards based on ISO 8601.
  • Implementation of the ISO 8601 Standard Around The World. [2002-01]
    List of countries adopting ISO 8601
  • International Writing [2002-01]
    Between Borders
  • ISO 8601 Dates: What They Are and Why They're Good [2002-01]
    Academic Computing and Communications Center
    Lots of good links
  • ISO 8601 Date/Time Representations [2002-01]
    A detailed description
  • ISO 8601 Converting [2002-01]
    NOTE: includes poll about using ISO 8601 on web sites
  • Open Directory [2002-01]
    Science: Reference: Standards: Individual Standards: ISO 8601
  • A Summary of the International Standard Date and Time Notation [2002-01]
    Markus Kuhn's classic description of ISO 8601
  • The Mathematics of the ISO 8601 Calendar [2002-03]
  • Keeping Up Standards [2002-02]
    Comments on ISO date and currency standards
  • Yahoo Groups: ISO8601 [2002-01]
    To bring the International Date and Time Format to the attention of the Internet world and beyond.
     

  • 2.4 Comments on other standards

  • SI Navigator [2002-03]
    Your Guide to the Modern Metric System (SI)
     

• 3. Organizations, Timekeeping

  (also see Technical Organizations)
   
• NIST: Time and Frequency Division [1994]
  maintains the standard for frequency and time interval for the United States, ...
  • The Official Time Of The U.S.A. [2001-12]
    Time and Frequency Division of the National Institute of Standards and Technology (NIST).
  • Glossary [2002-01]
  • Internet Time Service [2002-01]
  • Leap Second Information [1994]
  • Radio Station WWV (short wave) [2002-01]
  • Telephone Time [2002-01]
• IERS: International Earth Rotation Service [2002-02]
  is an interdisciplinary service that maintains key connections between astronomy, geodesy and geophysics. "The Leap Second people".
• NPL: National Physical Laboratory [2002-01]
  UK's keeper of time and frequency measurements
• The Royal Observatory Greenwich
  (more RGO in following sections)
  • Home Page [2002-01]
• USNO: U.S. Naval Observatory
  • Home Page [2002-01]
  • Time Server [2002-01]
    1
  • National Earth Rotation Service [2003-04]
    FAQ contaions much wonderful information
    • Differences of TAI and UTC as text file [2002-03]
      Difference between TAI and UTC on 1972-01-01 was 10 seconds
  
   

• 4. Non-Technical

  • 4.1 General

  • Open Directoy [2002-03]
    A truely wonderful list of links
  • Calendar FAQ by Claus Tøndering [2002-01]
  • Calendar Zone [2002-03]
    Lots of links to calendar facts
  • Date and Time Resources, Y2k and beyond [1996-11]
    • British Calendar Act of 1751 For The Year 1752 [2002-01]
      Actual text to the act
  • Home page for Calendar Reform [2003-05]
    • Papal Bull "Inter Gravissimas" (1582) [2003-06]
      Transcripts (Latin & English) of Pope Gregory XIII's Calendar reform of February 24, 1582
  • 
    2002-04
  • Allan's TIME [2002-09]
    Time Interval metrology Enterprise
  • Julian Day and Civil Date Calculator [2002-04]
    Julian Days to Gregorian Calendar Conversions
  • When Do You Want To Go Today? [2001-10]
    Many date, time, and calendar links.
  • The World Clock [2002-01]
    TimeAndDate.com: a guide to time zones, calendars, and more.
    Shows world time zones
     

  • 4.2 GPS

  • How accurate is the TIME DISPLAY on my GPS [2002-09]
    Important practicial information on GPS time
     

  • 4.3 Daylight Savings Time (a.k.a., Summer Time)

  • Full Text to American Daylight Savings Time Laws [2003-09]
    Web Exhibits.org
  • Studying the effects of Daylight Saving Time [2007-03]
    By DAWN SCHABBING, Staff Writer,gg-tc online
     

  • 4.4 Leap Seconds

  • U.S. Navel Obseravtory UTC Leap Second Survey [2008-09]
  • The Future of Leap Seconds [2007-05]
    Work in progress attempting to catalog all of the openly-available information about the process which may result in the discontinuation of leap seconds in radio broadcasts of time signals.
  • History of IEEEE P1003.1 POSIX time [2007-05]
    chongo (Landon Curt Noll)
  • 2005 Leap Second [2007-05]
    On the other hand, in 1 million years, about 15 leap seconds will be required each day.
  • Time and Time again [2007-05]
    Geek Trivia: What 1972 timekeeping innovation complicated the so-called UNIX epoch?
     

  • 4.5 Miscellaneous

  • CE :: AD / BCE :: BC [2002-01]
    A discussion of AD vs CE and BC vs BCE
  • Date and Time Week Numbers [2002-01]
  • The BDB Web Site [2003-03]
    Palindromic Dates
     

  • 4.6 Odd Stuff

  • Decimal Time [2002-01]
    Description of decimal time, including Julian Dates and metric time.
     

  • 4.7 Historic Information

  • The Royal Observatory Greenwich
    (other RGO links on this page)
     

  • 4.8 Millennium Change

  • The 21st Century and the Third Millennium [2002-01]
    U.S. Naval Observatory
  • Other Information
     

  • 4.9 Time Zones and International Dateline

  • Time Zones
  • Xerox Time zone Converter [2002-06]
  • Wikipedia - Time zones [1]
  • International Date Line
     

• 5. Technical

  • 5.1 Computer Science Links

    • 5.1.1 General

    • Date and Time Resources, Y2k and beyond [1996-11]
      • The British Calendar Act [2002-02]
        The 1751 law that change the British calendar in 1752
    • NTP: Network Time Protocol Home Page [2002-01]
      For the most accurate computer times (best results with 24-hour high speed connections to the Internet. See NTS above for dial-up)
    • zoneinfo files & programs home page [2002-01]
      Sources for Time Zone and Daylight Saving Time Data
    • Info on ISO 8601 [2002-01]
      Includes code fragments for various programming languages
       

    • 5.1.2 Macintosh

      
       

    • 5.1.3 Microsoft Windows®

    • DOS / Microsoft Windows dates vs RTC dates [2002-02]
      New Scientist 1997-11-08
       

    • 5.1.4 Internet

    • Date and Time on the Internet: Timestamps [2002-01]
      Internet Draft uses a profile of the ISO 8601 standard (The Internet Society) [2001-Nov, expires 2002-May]
       

    • 5.1.5 C

      
       

    • 5.1.6 Perl

      
       

    • 5.1.7 UNIX

    • Official UNIX Date Information and Year 2000 statement [2002-01]
       

  • 5.2 Daylight Savings Time (a.k.a., Summer Time)

  • Microsoft Official Daylight Saving Time Help and Support Center [2007-03]
  • Update Linux and FreeBSD systems for new Daylight Saving Time settings [2007-03]
  • Daylight Saving Time Material [2007-03]
    The Calendaring & Scheduling Consortium: many links to many vendors
     

  • 5.3 General

  • Open Directoy [2002-03]
    A truely wonderful list of links
  • What a Difference a Day's Length Makes [2002-03]
    How the length of a day on earth changes
  • Yahoo Science > Measurements and Units > Time [2002-01]
     

  • 5.4 GPS

  • GPS Date Rollover Issues [2002-01]
    From the U.S. Coast Guard Navigation Center
  • USNO GPS Time Transfer [2002-02]
    Among other subjects, why the GPS time is ahead of UTC time
     

  • 5.5 Organizations

  • International Astronomical Union. Information Bulletin No. 81. [2003-09]
    Resolution B1 for astronomers states Julian Day 0 is January 1 4713 BC.
     

• 6. Year 2000 Links

  Additional Y2k links not found elsewhere on this web page
   

  • 6.1 Computer Science

  • Year 2000 Information Center / Millennium Bug [1996-05]
    Peter de Jager's Y2k resource and service listings. Was major player during run up to Y2k for non-technical and technical resources.
  • Year 2000 References [2002-01]
    Lots of PC related issues and software downloads
     

  • 6.2 Other

  • Year 2000 and ISO 8601 [2002-01]
    Year 2000 Resource Centre for Amateur Radio operators and for Amateur Astronomers.
  • Buy A Bug [2002-01]
    St. Petersburg Times provides more information on year 2000 trademarks.
     

• 7. Year 2038 Links

• The Project 2038 Frequently Asked Questions (FAQ) [2006-10]
   

This information was gathered by Gilbert Healton for his personal use and is without warranty of any kind whatsoever. Use at your own risk.

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