Interesting post by Sukumar on the zaniness of daylight savings and time zones.
Of course, he neglects to mention Europe changes over a week before the US. Or the difference between GMT and UTC. Or that India thought multiple time zones would be too confusing for its population and just split the time. India is 5 and a HALF hours ahead of UTC. May be Indiana should adopt that too. China big as it is has only 1 time zone, though before the revolution in 1949 had 5. Russia has 11 time zones. Because the earliest and latest time zones are 26 hours apart, any given calendar date exists at some point on the globe for 50 hours.
Like Sukumar says it keeps the software industry employed. Makes global monthly closes fun for accountants. Allows airlines to collect change fees as passengers show up late. And keeps politicians busy.