What is Greenwich Mean Time, is there a layman s explanation, thank you

Local time on the Greenwich meridian, or time in the zero time zone (middle time zone), is called Greenwich Mean Time, also known as "Universal Time". Originally, Greenwich's flat noon was used as the beginning of a flat solar day, but it was somewhat inconvenient to use. However, the original Greenwich Mean Time (GMT) will remain as the UTC for the 21st century.

GMT is an abbreviation for "Greenwich Mean Time", Chinese called "Greenwich Mean Time", which is the standard time in the United Kingdom and the reference standard for time around the world.

Greenwich Mean Standard Time at the Royal Greenwich Observatory in the United Kingdom. Greenwich Mean Time is a form of expressing the rate of rotation of the Earth and is a system of time measurement based on the Earth's rotation, and the angle of the Earth's rotation can be measured by the motion of the local gamete meridian relative to the fundamental reference point on the Earth. <

Greenwich Mean Royal Greenwich Heaven's Standard Time. Greenwich Mean Time, a form of expressing the rate of rotation of the Earth, is a system of time measurement based on the Earth's rotation, and the angle of the Earth's rotation can be measured by the motion of the local meridian relative to the fundamental reference point on the Earth's Cathol.

Greenwich Mean Time is the standard time at the Royal Greenwich Observatory in the United Kingdom. Greenwich Mean Time, a form of expressing the rate of rotation of the Earth, is a time measurement system based on the Earth's rotation, and the angle of the Earth's rotation can be measured by the motion of the local meridian relative to the fundamental reference point on the Earth.

Universal time, or Greenwich Mean Solar Time, refers to the standard time in the location of Greenwich. Prior to 1960, universal time was considered to be a uniform time.

In order to measure the rotation of the Earth, two basic reference points were chosen on the Earth: the vernal equinox (see equinox solstice) and the Flat Sun Point, and the times determined by this are called sidereal time and Equilibrium Solar Time, respectively.

Greenwich Mean Standard Time at the Royal Greenwich Observatory in the United Kingdom. Greenwich Mean Time is a form of expressing the rate of rotation of the Earth, and is a time measurement system based on the rotation of the Earth, and the angle of the Earth's rotation can be measured by the motion of the local meridian relative to the fundamental reference point on the Earth.

Local time on the Greenwich meridian, or time in the zero time zone (middle time zone), is called Greenwich Mean Time, also known as "Universal Time". Originally, Green imitated the flat noon of Wich as the beginning of a flat solar day, but it was somewhat inconvenient in use. As a result, the International Astronomical Union (IAU) decided in 1928 to use mean solar time, which is commonly known as Greenwich Mean Time, as Universal Time, which is commonly known as Greenwich Mean Time.

On December 28, 1999, a new time system, Greenwich Electronic Time (GET), was officially born, which will provide a time standard for global e-commerce. The original Greenwich Mean Time (GMT) will remain as the UTC for the 21st century.

Greenwich Mean Time refers to the standard time at the Royal Greenwich Observatory located in the suburbs of London, England, as the prime meridian is defined as the meridian that passes through there.

Theoretically, noon in GMT refers to the time when the Sun crosses the Greenwich Meridian (i.e., GMT). Due to the uneven speed of the Earth's motion in its elliptical orbit, this moment may differ from the actual solar time by 16 minutes.