Learn About Time Zones
Guides and articles about time zones, UTC, Daylight Saving Time, and best practices for scheduling across the globe.
Fundamentals
What is UTC and Why Does It Matter?
Learn about Coordinated Universal Time (UTC), the global time standard that keeps the world synchronized. Understand how UTC works and why it matters for travel, technology, and communication.
Understanding Daylight Saving Time (DST)
A complete guide to Daylight Saving Time — why we change clocks, which countries observe DST, when transitions happen, and how DST affects timezone conversions.
How Time Zones Work: A Complete Guide
A comprehensive guide to how time zones work — from UTC offsets and DST to political boundaries and unusual half-hour zones. Everything you need to understand global timekeeping.
GMT vs UTC: What's the Difference?
GMT and UTC are often used interchangeably, but they are technically different. Learn the key differences between Greenwich Mean Time and Coordinated Universal Time.
What is the International Date Line?
Learn about the International Date Line — the imaginary line where the calendar date changes. Understand why it exists, where it runs, and how it affects travel and communication.
Half-Hour and Quarter-Hour Time Zones
Not every time zone falls on a whole hour. Discover why India is UTC+5:30, Nepal is UTC+5:45, and other countries use fractional offsets that confuse travelers and programmers alike.
Timekeeping on the Moon and Beyond Earth
The International Space Station runs on UTC, but what about the Moon or Mars? Explore how timekeeping works in space, why we might need a lunar time zone, and the physics that makes clocks tick differently off Earth.
Will We Ever Abolish Time Zones?
Some scientists and economists have proposed scrapping time zones entirely and putting the whole world on UTC. Explore the arguments for and against abolishing time zones, and what the practical consequences would be.
Practical Guides
Time Zone Abbreviations Explained
A guide to timezone abbreviations like EST, PST, GMT, CET, and IST. Learn what they mean, why some are ambiguous, and when to use IANA timezone names instead.
Best Practices for Scheduling Across Time Zones
Practical tips and strategies for scheduling meetings, calls, and events across multiple time zones. Avoid common pitfalls and find the best times for global teams.
Jet Lag and Time Zones Explained
Jet lag is more than just tiredness. Learn how crossing time zones disrupts your circadian rhythm, why eastward travel is harder, and evidence-based strategies to recover faster.
Working Across Time Zones for Remote Teams
Remote work across time zones brings unique challenges. Learn practical strategies for async communication, overlap hours, meeting fairness, and building team culture when your colleagues are spread around the globe.
Military Time and NATO Time Zones Explained
From Zulu time to Alpha and Mike, the military uses a phonetic alphabet system to label time zones around the world. Learn how NATO time zones work, why Zulu means UTC, and when this system is used today.
How Computers Handle Time Zones
Time zones are one of the trickiest problems in software. Learn how the tz database works, why you should store UTC, what Unix timestamps actually represent, and the common pitfalls that catch even experienced developers.
History
History of Time Zones
Explore the fascinating history of time zones — from local solar time to the global system of 24 standard zones. Learn how railroads, telegraphy, and international cooperation shaped modern timekeeping.
Why Japan Doesn't Use Daylight Saving Time
Japan tried Daylight Saving Time and rejected it. Learn why Japan stopped observing DST after World War II, how Japanese culture shaped the decision, and what it means for travelers and businesses.
Why China Uses a Single Time Zone
China spans five geographical time zones but uses only one: UTC+8. Learn the political history behind this decision, how it affects daily life in western China, and the unofficial time zones that have emerged.
Countries That Switched Time Zones
From Samoa skipping a day to North Korea inventing its own time, countries have changed their time zones for politics, economics, and national pride. Here are the most dramatic switches and their consequences.