1. Definition:
JSON (JavaScript Object Notation, JS Object Notation) is a lightweight data interchange format.
2. Features:
It is based on a subset of ECMAScript (the js specification developed by the European Computer Association) and uses a text format that is completely independent of the programming language to store and represent data.
3. Advantages:
(1) Concise and clear hierarchical structure makes JSON an ideal data exchange language.
(2) It is easy for humans to read and write, but also easy for machines to parse and generate, and effectively improve the efficiency of network transmission.
4. Grammar rules:
In the JS language, everything is an object
. Therefore, any supported type can be represented by JSON, such as strings, numbers, objects, arrays, etc. But objects and arrays are two special and commonly used types:
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Objects are represented as key-value pairs
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Data is separated by commas
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Curly braces hold the object
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Square brackets hold arrays