GMT: what can we remember?

Not all countries in the world use the same time system. And for your information, there are several types of time: the mean time, the solar time, the automatic time... So we hear UTC and GMT. But if we take GMT, what can we understand?

Mean time (GMT): meaning and how it is used

Only a few centuries ago, our grandparents used the stars and the sun to be able to locate the time. But as the world evolved, time systems appeared. Among these systems, there is the mean time, commonly called GMT. GMT is a time zone set up by Greenwich. But the full name is Greenwich Mean Time, which earned the sobriquet "GMT" to this time system. You can find more information about the origin of the GMT time system on our next page. However, what can we learn about how it is used? To talk about how GMT mean time is used, we should also talk about the difference between GMT and solar time. The GMT is the one that is still called the clock time. It is a time that does not vary. But the solar time is variable because it takes time to cross the meridian line. This is what shifts the average time from the solar time. The clock always indicates the same time everywhere, the same minutes and the same seconds. But if we take into account the solar time, we have to add or subtract hours. That's why in some countries, while it is 20h, in others it can be 22h, 23h, 00h ...

What countries use mean time (GMT)?

There are several countries that use GMT. We will just list a few. In this year 2021, despite the big trend of UTC time, some countries such as the United Kingdom, Australia, South Africa, New Zealand, India, Pakistan, Malaysia, Ireland, Isle of Man, Greenland, Iceland... still use GMT. However, GMT and UTC are almost the same since it is the same day (24h).