The time change is an operation which consists of moving the clocks forward or backward by one hour in order to take advantage of one hour more or less of sunshine. It takes place on the last Sunday of October and last Sunday of March.
The transition to summer time is a system consisting of adjusting the official local time, by adding one hour to that of the so-called normal time zone (which prevails in winter).
In fact France had adopted summer time from 1916 following Germany, then had decided in 1945 to abandon the principle of the time change… but by keeping summer time, that is to say the one who had been moved and not that of winter which corresponded to the meridian of Greenwich.
We also speak of this fact as double summer time because our countries are already one hour ahead of the meridian of Greenwich, while we are at the same longitude. So when it should be noon according to solar time, that is to say that the sun is at its zenith, our clock already displays 2 p.m….
In Europe, daylight saving time begins on the last Sunday in March and ends on the last Sunday in October.
