Time Zones
- Time zones are geo-political entities
- completely arbitrary, can change at a politician's whim
- Canonical data source: the Olson time zone database
- Each time zone has several parts
- an offset from UTC in minutes and hours
- a name - usually continent or ocean plus city
- America/Toronto
- Europe/London
- some have three component names - America/Indiana/Knox
- Also includes Daylight Saving Time rules
- when do switches happen
- a short name for the zone, like EST