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JSON: What is it and How to Use It?

JSON, a data format created for JavaScript applications, stands for JavaScript Object Notation. The primary purpose of JSON is to facilitate data exchange with smaller data payloads.

JSON encompasses five data types:

  1. Number
  2. String
  3. Array
  4. Boolean
  5. Object
  6. Null

Data in JSON consists of two parts: key and value. The key defines which property of the object it is (akin to a variable name in code), while the value defines the actual value of that property (similar to the variable's value in code).


  • Compact Data Exchange: JSON excels at minimizing data size during data exchange, enhancing efficiency.
  • Language-Agnostic: Being independent of programming languages, JSON is versatile and widely compatible.
  • Human-Readable: JSON's structure is easy to read and understand, fostering clarity in data representation.
  • Easy to Parse: JSON data can be easily parsed and converted into native data structures in various programming languages.

Professional Example: Consider a scenario where a web application needs to exchange user data between the frontend and backend. JSON can be employed to structure this data:

  "user": {
    "id": 147,
    "username": "tahsinsoyak",
    "email": "",
    "preferences": {
      "theme": "dark",
      "notifications": true
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In this example, keys like "id," "username," and "preferences" represent different properties of the user object, while values provide corresponding data. JSON's simplicity and clarity make it an ideal choice for such data exchange scenarios.

One more example: E-Commerce -  Product Information
Consider an e-commerce platform that needs to exchange product information between the server and the user interface. JSON can be utilized to represent a product's details:

  "product": {
    "id": "ABC123",
    "name": "Smartphone",
    "brand": "Suntheo",
    "price": 499.99,
    "specifications": ["4GB RAM", "128GB Storage", "Dual Camera"]
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Below is a simple example of a Flask application that handles a GET request and returns the provided JSON response:

from flask import Flask, jsonify

app = Flask(__name__)

# Sample product data
products = {
    "ABC123": {
        "name": "Smartphone",
        "brand": "Suntheo",
        "price": 499.99,
        "specifications": ["4GB RAM", "128GB Storage", "Dual Camera"]
    # Add more products as needed

@app.route('/product/<string:product_id>', methods=['GET'])
def get_product(product_id):
    # Check if the product ID exists
    if product_id in products:
        return jsonify({"product": {product_id: products[product_id]}})
        return jsonify({"error": "Product not found"}), 404

if __name__ == '__main__':
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  • The /product/string:product_id endpoint is defined to handle GET requests with a dynamic product_id parameter.
  • The get_product function checks if the provided product_id exists in the products dictionary and returns the corresponding product data if found. Otherwise, it returns an error response with a 404 status code.

Now, you can test different product IDs by visiting URLs like:

If you need further information or have specific questions, feel free to ask! Tahsin Soyak

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