Not everyone sticks to the "one-hour" rule. Countries like India, Iran, and Afghanistan use offsets that include 30-minute increments (e.g., IST is UTC+5:30).
Before the mid-19th century, time was a local affair. Every town set its own clocks based on —the moment the sun reached its highest point in the sky. While this worked for agricultural societies, the Industrial Revolution and the birth of the railroad made "local time" a nightmare.
From the steam engine to the satellite, the time zone remains one of humanity's most successful (and occasionally frustrating) attempts to synchronize our lives with the rotation of the planet.
In a world that never sleeps, the concept of a is the invisible thread that keeps our global society organized. Whether you are catching a flight, hopping on a Zoom call with a colleague overseas, or simply wondering why the sun is setting while your friend is eating breakfast, time zones dictate the rhythm of modern life.
The primary time standard by which the world regulates clocks. It is the successor to GMT (Greenwich Mean Time) and is highly precise, kept by atomic clocks.
But where did this system come from, and why is it so much more complicated than just looking at the sun? The Death of "Solar Time"
However, geography rarely follows clean lines. Time zone boundaries are often jagged, swerving to accommodate national borders, political preferences, or economic ties. Key Terms to Know
