JSON is a simple interchange format, but its syntax is stricter than JavaScript object literals. Keys and string values need double quotes.
Objects and arrays
JSON objects hold named properties, while arrays hold ordered values. Common types include strings, numbers, booleans and null.
Frequent errors
Trailing commas, unquoted property names, single-quoted strings and comments are not valid in standard JSON.
Formatting for readability
Pretty-print data while developing, and prefer compact payloads when transferring large amounts of data. Always check that parsing succeeds.
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