The ddhhmmss Blog
Stories and explainers about time — the history of time zones, DST, Unix time, leap years, focus techniques and the world’s strangest clocks.
Golden Hour Is Rarely an Hour
Why the best light lasts 20 minutes at the equator and half the evening in Scotland — and how to plan a shoot around the sun’s actual angle.
GuidesBusiness Days vs Calendar Days: Why Your Deadline Moved
“Within 10 business days” can mean anywhere from 12 to 18 calendar days depending on the month, the country and whose weekend you mean.
ExplainersWhy the Moon Has Phases (and Why It Isn’t Earth’s Shadow)
The most common astronomy misconception, cleared up — plus why the same moon looks upside down in Sydney and Stockholm.
ExplainersWhy 03/04/2026 Means Two Different Days
Month-first, day-first or year-first? The world writes dates three incompatible ways. Here is the map, the history, and the one format that ends the confusion.
ExplainersWhat Is a UTC Offset? (And Why India Is +5:30)
Time zones are just offsets from UTC — but they range from −12:00 to +14:00, some are half-hours, two are 45 minutes, and one country spans none of it.
GuidesHow to Schedule Across Time Zones Without Getting It Wrong
A practical checklist for booking calls across continents — the traps that cause 90% of mistakes, and the habits that prevent all of them.
HistoryWhy Do Time Zones Exist? A Short History of Standard Time
Before the 1880s every town kept its own solar time. Railways, telegraphs and one 1884 conference in Washington gave us the time zones we use today.
ExplainersDaylight Saving Time, Explained: Why Clocks Spring Forward
Who invented DST, why wartime made it real, why the dates differ by country — and why half the world never changes its clocks at all.
DeveloperWhat Is Unix Time? The Number Behind Every Timestamp
Unix time counts the seconds since 1 January 1970 UTC. Here is why that date was chosen, how the Year 2038 problem happens, and how to read timestamps.
CuriositiesThe World's Strangest Time Zones
Half-hour offsets, a +14 hour island nation, the country that skipped a whole day, and why China runs on one clock — a tour of time-zone oddities.
ProductivityThe Pomodoro Technique: A Practical Guide to Focused Work
How the 25-minute tomato timer works, why timeboxing beats willpower, and how to adapt Pomodoro intervals to study sessions and deep work.
ExplainersLeap Years, Leap Seconds, and Why Calendars Drift
Earth takes 365.2422 days to orbit the sun — and that awkward fraction explains leap years, the 1582 calendar reform, and the death of the leap second.
ExplainersHow Many Weeks Are in a Year? (Hint: Sometimes 53)
A year is 52 weeks and a bit — and under ISO 8601 some years officially have 53 numbered weeks. 2026 is one of them. Here is how week numbering works.
HistoryWhy Does February Have 28 Days?
Blame the Romans: an unlucky number, a purification month, and a calendar that once simply skipped winter. The strange story of the shortest month.
ExplainersGMT vs UTC: What’s Actually the Difference?
They usually show the same time, but GMT is a solar time from the 1800s and UTC is an atomic standard. Which one should you use — and when?
HistoryWhy Are There 60 Minutes in an Hour and 60 Seconds in a Minute?
Our clocks count in base 60 because Babylonian astronomers did — and 60 divides beautifully. The 4,000-year story hiding on your watch face.