What is JSON?

What is JSON?

JSON (JavaScript Object Notation) is a lightweight text format for storing and sharing data. It is the standard for sending data between web servers and browsers.

JSON looks like an object

{
  "name": "Ada",
  "age": 36,
  "languages": ["English", "French"]
}

The rules of JSON

• Data is in name/value pairs.
• Names must be in double quotes.
• Values can be strings, numbers, booleans, arrays, objects, or null.
• Commas separate pairs.
• Curly braces hold objects, square brackets hold arrays.

JSON is language independent

Even though it comes from JavaScript, JSON works with every language: Python, C#, Java, and more. That is why it is so popular for APIs.

JSON vs JavaScript object

• JSON names MUST be double quoted.
• JSON is always text (a string).
• No functions or undefined allowed.

TL;DR

• JSON is a text format for data.
• Names are double quoted.
• Values: strings, numbers, booleans, arrays, objects, null.
• It works across all programming languages.