What is JSON? Complete RFC 8259 Standard Guide
Comprehensive overview of JSON data interchange format, syntax specifications, supported data types, and why it replaced XML.
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JSON (JavaScript Object Notation), standardized in RFC 8259, is the de facto standard for data exchange across the modern internet. Virtually every REST API, GraphQL service, and NoSQL database uses JSON to serialize and transfer structured information.
The Six Supported JSON Data Types
1. Object: An unordered collection of name/value pairs enclosed in `{}`.
2. Array: An ordered sequence of values enclosed in `[]`.
3. String: Text enclosed in strict double quotes (`"text"`).
4. Number: Double-precision floating-point numbers (e.g. `42`, `3.14159`, `-10`, `1.2e5`).
5. Boolean: Exact literals `true` or `false`.
6. Null: The exact literal `null`.
What JSON Does Not Support
Unlike JavaScript objects, standard JSON does not support functions, undefined, NaN, Infinity, single-quoted strings, or unquoted property names.
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