A Field Guide to Time
Dates & times in programming, demystified. It is organized into five sections, from human concepts down to standards and patterns. Start anywhere — each topic begins gently and deepens.
New here? Begin with Concepts & human language for the mental model, then dip into your language when you need code.
Concepts & human language
What dates, times, instants, and zones actually mean — before any code.
11 topics
In programming languages
How real languages and libraries model time, with runnable examples.
9 topics
Storage & interchange
Persisting and exchanging time across databases, formats, and the wire.
5 topics
Standards
The specs underneath it all — ISO 8601, RFC 3339, the IANA tz database, and friends.
4 topics
Functional patterns
Reusable approaches for handling time correctly in practice.
11 topics