Learning
What is JSON?
JSON is a lightweight data format for objects, arrays, strings, numbers, booleans, and null.
Last updated 2026-07-12 · 4 min read
Why developers use JSON
JSON is easy for humans to read and easy for software to parse, which makes it common in APIs, configuration files, logs, and test fixtures.
Common mistakes
Trailing commas, comments, and unquoted keys are not valid JSON even though some adjacent formats allow them.