Attempt at global Standard Time.
Handy tool/site for lining up: http://www.worldtimebuddy.com/
Note that Time Zone-s don't follow borders
- in the US, a number of states are split across Time Zone-s
- many other countries are split across Time Zone-s also
DST is a nightmare: see http://www.webexhibits.org/daylightsaving/index.html
- UTC is the Coordinated Universal Time, which does not move for Daylight Savings Time (DST).
- GMT does move, though when moved it's not actually called GMT, but rather BST (British Summer Time).
- Some parts of the US (e.g. Arizona, Hawaii) don't do DST.
- Of those parts of the US that do DST, they don't switch on the same date as the GMT/BST switch.
- Oct'2009: interesting Jon Udell look at some historical info
- for US-only situations, there are still only a relatively small number of values you need to support (although the full reference db includes many redundant values).
- but for outside the US, you need to include a huge number of values.