Time zones sometimes seem positively eccentric, affected as they are by political, geographical and social changes in the real world. But as irregular as they are, if you want to divide the world up into time zones, you need a way to measure time.

Review rich online resources on time zones from BBC News. Did you know we have a we have a time zone lesson already written and ready to implement in your class room in our 20 Minute GIS book?

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