The gmt full form is  Greenwich Mean Time.
G = Greenwich
M = Mean
T = Time
At the Royal Observatory at Greenwich, London, it is mean solar time. It is measured on the Earth’s zero-degree longitude line (meridian). This line connects the North and South Poles, passing through Greenwich, London’s Old Royal Observatory. Greenwich Mean Time (GMT) is the international time standard. It was founded in the year 1884 and is used as a global standard to scale all the time. It serves as a reference point for all time zones.
Greenwich Mean Time is a time zone that spans the globe. It is the foundation of global time. This is a precise time stamp. It isn’t affected by the seasons. If a country is east of the Greenwich Meridian, its local time is ahead of GMT; for example, China’s local time is GMT+8 hours. Similarly, if a country lies west of the Greenwich Meridian, its local time is behind the GMT; for example, New York’s local time is GMT? 4 in the summer and GMT -5 in the winter.
- GMT was not formally adopted by the British Parliament until August 2, 1880.
- On November 18, 1883, the United States of America ratified it.
- GMT was established worldwide in 1884 at the International Meridian Conference, and 24 time zones were established.
- Today, the United Kingdom’s civil time, or UTC, is known as GMT.
- GMT is regarded as a global time standard. It was established in 1884 and is used as a reference for global timelines and as a standard for all time zones.
- Greenwich Mean Time is also known as Greenwich Meridian Time since it is calculated from the Greenwich Meridian Line.
- It is focused on the uneven rotation of the planet, but it uses a hypothetical mean and accounts for a uniform velocity near the equator.
- GMT stands for Greenwich Mean Time and is the foundation of world time. It is a precise time reference that does not change with the weather.