What is JSON, How to Read, Write and Validate JSON Correctly

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate. It is the standard format used by APIs worldwide.

JSON Structure

JSON has two core structures: Objects (key-value pairs in { }) and Arrays (ordered lists in [ ]).

Data Types

• String: "text" — must use double quotes
• Number: 42, 3.14
• Boolean: true or false
• Array: [1, 2, 3]
• Object: {"key": "value"}
• Null: null

Common Mistakes

• Using single quotes instead of double quotes ❌
• Trailing commas after the last item ❌
• Unclosed brackets or braces ❌

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