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Everything About Time Zones
Articles covering the basics, clock changes, scheduling across time zones, and the technical details behind how computers handle time.
IANA Time Zone Database Explained
The IANA tz database is the source of truth for time zone rules used by virtually every operating system and programming language. Here's how it works.
Deep DivesUTC vs GMT: What's Actually Different?
UTC and GMT are often used interchangeably, but they're technically distinct. Here's what separates them and when the difference actually matters.
Deep DivesUnix Time vs UTC
Unix time is the number of seconds since January 1, 1970 — but it's not the same as UTC. Here's how Unix timestamps work and why they ignore leap seconds.
Deep DivesISO 8601 Date and Time Format Explained
ISO 8601 is the international standard for representing dates and times in software. Here's how to read and write it correctly, and why it matters.
Deep DivesHow Computers Handle Time Zones
From the system clock to what's displayed on your screen, here's the full chain of how operating systems and applications manage time zone conversions.
Deep DivesWhat Is a POSIX Time Zone String?
POSIX TZ strings like 'EST5EDT,M3.2.0,M11.1.0' encode time zone rules in a compact format. Here's how to read them and when you'll encounter them.
Deep DivesNTP: How Computers Stay in Sync
The Network Time Protocol keeps billions of computers' clocks accurate to within milliseconds of each other. Here's how it works and why it matters.
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