Time zones, explained properly
Short, useful articles about the numbers people get wrong — from TV diagonals that do not match the wall to luggage that misses the limit by a kilo.
Why your recurring meeting moves by an hour twice a year
The US changes its clocks three weeks before the EU. For those three weeks, every standing transatlantic meeting is in the wrong slot — and almost nobody notices until someone misses it.
IST means three different things and your invitation does not say which
India Standard Time, Irish Standard Time and Israel Standard Time all abbreviate to IST — and they are up to four and a half hours apart.
UTC is not GMT, and in summer the difference bites
For seven months a year the UK is not on GMT at all. Teams that treat the two as interchangeable end up with incident timelines an hour out.
Most of the world does not change its clocks
Around 70 countries change their clocks. The majority of the world's population does not — including India, China, Japan, Brazil and Russia.
How to run a meeting across eight time zones
Past about eight hours of spread there is no comfortable slot. The question stops being "when" and becomes "whose turn is it".
Landing before you took off: the date line explained
A Tokyo–Los Angeles flight lands six hours before it took off, by the clock. Nothing strange happened to the aircraft.
The five time zone bugs that reach production
Almost every timezone bug is one of five mistakes. All five are avoidable with rules that fit in a paragraph.
What time the markets really open in your zone
The New York open is at 2:30pm UK time — except for about four weeks a year when it is at 1:30pm and everyone is briefly wrong.
The long argument about abolishing clock changes
The EU voted to abolish seasonal clock changes in 2019. Seven years later, nothing has changed — and the reason is more interesting than inertia.
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