There has been some form of daylight savings time in the United States since World War II, when it was called "war time." When I was a kid, every state had its own rules for whether or not to observe it, and the dates when it began or ended. In 1966 they finally passed a law that said that a state could decide whether or not to observe it, but that all the states that observe it had to use the same starting and ending dates.

48 of the 50 states observe it, Arizona and Hawaii do not.

The (rather clever IMHO) saying "Spring ahead, fall back" reminds everyone which way to change their clocks--set them ahead an hour in the spring, set them back an hour in the fall. "Spring" and "fall" are the names of the seasons, but "spring" can also mean "jump" (suggesting forward movement), and while the phrase "fall back" can mean "retreat."

In Thailand, hasn't daylight saving time.

No. it was canceled a few years ago. As more accurate answer is possible... I'll give it. So:

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Shift in sunset/sunrise with respect to Greenwich is (longitude/15) hours, right? (15=360/24)

So 'nautical time zones', which are purely geographical, run in 15 degrees-wide stripes, where 0-time zone lies 7.5 degrees east and 7.5 degrees to west from Greenwich meridian.

Compared with this 'nautical time', most of Russian regions are roughly (very roughly) correspond to 'nautical'+1. Though Moscow (~37.3-37.8°E) managed to lie exactly on the border or two 'nautical' time zones. So a few minutes of walking west from my home my watches show nautical+1, a few to east my time would be 'nautical'.

If we call 'natuical time' + 1  'summer time', then nautical time itself is 'winter time'.
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They fiddled with the time (in particular, daylight saving time) soon after the revolution in 1917-22.
Then we had time close to nautical one.

Since 1930 they started to use double terminology: they kept old names for time zones, but clocks  were mostly set as +1. (so called 'decree time').

In 1981 they introduced daylight saving time, which lasted to 2011.
Since then we called daylight saving time ('timezone+2') 'summer time', and timezone+1 'winter time'

When Russia got its independence from USSR (whatever it means:)) in 1991. they fiddled for a while with time again in 1991 and 1992.

In 2011  president Medvedev canceled yearly transitions, and the country stuck in 'summer time' (which is esseially 'double summer time').

In 2014 fall Putin changed it into 'winter time' (wich is more or less summer time).

Personally I

- get used to daylight saving time:)
- find it funny
- would prefer is such desisions were taken differnt way...

Our clock hasn't changed yet. It's ok though... it's so cold outside I doesn't matter!!

yeah... At the first of Spring, 21st of March