World clock

The Urania world clock on Alexanderplatz in Berlin .
Design: Erich John

Mechanical wristwatch with world time indication ( Heures Universelles )

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A world clock is a clock that shows the time in several or all of the world's time zones . While world time clocks have mainly consisted of larger installations in the past few years, more and more digital models have existed for some years, some of which also fit on a desk or even on the wrist and take the possible date change into account. There are also various websites dealing with the topic on the Internet.

The simple division into 24 time zones (in which, starting from the zero meridian through Greenwich, the time shifts by one hour after every 15 degrees of longitude) was made more difficult by locally deviating daylight saving time changes, with the addition of half-hourly steps (especially for the Asian region ) to 36 time zones expanded.

literature

• Gisbert L. Brunner : World time clocks. In: The man. Magazine. No. 2, 1991, pp. 76-78.

Web links

Commons : World Clocks  - Collection of pictures, videos and audio files

Wiktionary: World clock  - explanations of meanings, word origins, synonyms, translations

• World clock / time zone map
• 36 time zones at a glance
• World clock / time zone map
• World clock / time zone map with time change
• Time zones and information

Individual evidence

1. ^ Helmut Kahlert , Richard Mühe , Gisbert L. Brunner , Christian Pfeiffer-Belli: wrist watches: 100 years of development history. Callwey, Munich 1983; 5th edition, ibid. 1996, ISBN 3-7667-1241-1 , p. 506 ( world time indication ).