When it’s 1pm in Rwanda, it is 2pm in the neighbouring East African countries of Kenya and Uganda. In another continent, such as North America, it’s early morning. This is because the countries are in different time zones.
In early centuries, after time keeping instruments were invented and time keeping had advanced from the use of sundials, different parts of the world had their own way of estimating time. For instance, according to ThoughtCo, a knowledge resource, there were places with town clocks which would set the time to midday whenever the sun reached its zenith. People would then set their personal clocks or pocket watches based on the town clock.
When trains were invited and people started to travel long distances, it became important to have standard time because travellers were being confused by the different local times. This is according to History, an information dissemination platform.
Creation of time zones was then proposed by Canadian engineer and inventor Sir Sandford Fleming in 1878. This is according to ThoughtCo. Fleming proposed dividing the world into 24 time zones that are 15 degrees of longitude apart.
The reason behind Fleming’s suggestion, according to Wikipedia, an encyclopaedia, is that since each day comprises 24 hours and since there are 360 degrees of longitude, this means that every hour, the earth rotates one twenty-fourth of a circle. And one over twenty-four multiplied by three hundred sixty is fifteen.
The idea was first implemented by railroad companies of the United States on November 18, 1883, and the following year in October, the standardisation of time was established during the International Prime Meridian Conference. According to the online knowledge resource on time, World Time Server, during the conference, England was selected as zero degrees longitude and the Greenwich Mean Time (GMT) was established as the standard time.
According to the Time and Date online information platform, GMT was later replaced by Coordinated Universal Time (UTC) in 1972 as the world standard time.
Although time zones are now implemented around the world, they are not used exactly as was calculated by Fleming. For instance, all of China uses one time zone even though the country extends to five time zones. However, according to Web Exhibits, an information resource in some countries such as the United States, states have differing time zones.
This is to say that a time zone is not necessarily an accurate representation of time. It is, according to Wikipedia, “a region of the globe that observes a uniform standard time for legal, commercial, and social purposes.”