J
JSON & APIs
Learn JSON syntax, parse and build data structures, and explore how REST APIs work interactively.
Web Development
v1.0.0
Free
283 uses
J
JSON & APIs
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Step 1: JSON Syntax
JSON (JavaScript Object Notation) is a lightweight data format used everywhere on the web. It supports six data types:
- Strings — wrapped in double quotes:
"hello" - Numbers — integers or decimals:
42,3.14 - Booleans —
trueorfalse - Arrays — ordered lists:
[1, 2, 3] - Objects — key-value pairs:
{"name": "Alice"} - Null — empty value:
null
Edit the JSON below, then click Validate to check if it's valid:
About This Lab
JSON (JavaScript Object Notation) is the universal data format of the web. In this lab, you'll learn JSON syntax, practice parsing and building JSON structures, and understand how REST APIs use JSON to exchange data between clients and servers.
How It Works
- 1 Read each step's explanation of JSON and API concepts
- 2 Edit JSON in the interactive editor and validate it
- 3 Explore the mock API to see request/response patterns
- 4 Complete the quiz to test your understanding
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