📄 Lesson: What is JSON?

Understanding JSON Structure & Syntax

Learning Objectives:

📋 What JSON stands for and what it is
🏗️ Understand JSON's two main structures
🔤 Learn JSON data types
📝 Master JSON syntax rules

🤔 What is JSON?

JSON = JavaScript Object Notation

📝 Text-based data format - Just plain text
🌐 Language independent - Works with any programming language
📱 Lightweight - Minimal syntax, easy to read
🔄 Data exchange standard - How systems share information

Important: Despite the name "JavaScript", JSON is used by ALL programming languages - Python, Java, C#, PHP, etc.

🏗️ JSON Has Only 2 Structures

Everything in JSON is built from these two simple structures:

📦 OBJECTS

Collection of key-value pairs

                        { "key": "value" }
                    

📋 ARRAYS

Ordered list of values

                        [ "value1", "value2" ]
                    

                That's it! Every JSON document is either an object, an array, or a combination of both.
            

📦 JSON Objects

Objects store data as key-value pairs inside curly braces { }

📝 Editable JSON Object Example

Object Rules:
• Wrapped in curly braces { }
• Keys must be strings (in quotes)
• Key and value separated by colon :
• Pairs separated by commas ,

📋 JSON Arrays

Arrays store ordered lists of values inside square brackets [ ]

📝 Editable JSON Array Example

Array Rules:
• Wrapped in square brackets [ ]
• Values separated by commas ,
• Can contain any data type
• Order matters (first, second, third...)

🔤 JSON Data Types

JSON supports exactly 6 data types:

String
"GBPUSD"

Number
1.35084

Boolean
true/false

Null
null

Object
{ }

Array
[ ]

📝 Try All Data Types

📝 JSON Syntax Rules

JSON has strict rules that must be followed:

✅ Keys must be strings - Always in double quotes
✅ Use double quotes - Never single quotes
✅ No trailing commas - Last item has no comma
✅ No comments allowed - Pure data only
✅ Case sensitive - "Symbol" ≠ "symbol"

❌ WRONG

✅ CORRECT

🎯 What You've Learned

                JSON Structure Fundamentals:
                ✅ JSON = JavaScript Object Notation
✅ Two main structures: Objects { } and Arrays [ ]
✅ Six data types: string, number, boolean, null, object, array
✅ Strict syntax rules must be followed

            

🚀 Practice Area - Try Your Own JSON!

🚀 Next: We'll see how this structure works with real trading data!