the world with 24 segments signifying the different time zones

Time zones were created to standardize the way we communicate time

OCT 26, 2014

Time and time zone are a human invention. It helps us track, compare and organize our days in a way that is easy to understand and communicate. Over the ages the way we tell time has changed, largely in part of the need to communicate it faster, more accurately and with more of us around the world.

Sundials were a great way to tell time locally

sundialBefore mechanical timekeeping was invented, settlements would keep track of time locally based on the position of the sun throughout the day. Sundials, for example, provided the ability to tell time by tracking the shadow of the would fall onto a dial. A great method, people used this to communicate time for decades with some accuracy and worked very well within the confines of a small geographical location.

When mechanical clocks became more accurate during the 1900s, cities began keeping track of time with the Mean solar time method which measured days of equal length and at the end of the year, averaged any discrepancies to 0.

As traveling and communication became easier keeping track of time locally became ineffective

As quicker means of transportations were invented and people began to travel more keeping track of time based on the 1 city became less effective. Local time keeping would mean two cities not too far from each other would have different times, causing confusion when scheduling railway timetables and cross-city communication.

people the next time over would be in a different time, making collaboration more difficult

The world needed to agree on a standard way of communicating time.

The Greenwich Mean Time (GMT) was invented for mariners and adapted as the global method to standardize global time

Greenwich Mean Time(GMT) was invented by the Royal Observatory in England to aid mariners by providing a standard way of telling time. By providing a consistent way to tell time independent of the cities, Mariners were able to more accurately communicate their positions and arrival times. Though their were other methods, GMT was considered the most accurate, most widely used, and kept record for longest time, so In 1884 GMT was accepted as the time standard for the world. Eventually replacing local times.

GMT pictures the world as a 360 degree circle and breaks it up into 24 regions with 1 hour difference per region

GMT works by establishing an invisible start point at 0 degrees at the Greenwich Meridian and tells time by subtracting or adding based on the distance from that start point. The time is calculated depicting the world as a circle with 360 degrees in longitude, then divides it into 24 regions. Each region equals a difference of 1 hours from the beginning point. Time to the eastern of the Meridian is referred to as "ahead GMT", while the western side is called "behind GMT".

The 24 regions that make up GMT, are called time zones

Today time zones have been adapted for the ease of a region's inhabitants and may not exactly correlate with the GMT. For example, even though China crosses 15 degrees in longitude, it uses the same consistent time this makes it easier for China's inhabitants to communicate time.

About the author
Venessa Perez has been creating digital experiences for over 14 years and has formed, cultivated, and grown virtual teams of developers, designers, and user experience architects for over 5 years.

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