CSV and JSON Basics¶

Many programs exchange data using common text formats such as CSV and JSON.

These formats allow data to be stored and shared between systems.

flowchart LR
    A[Program] --> B[CSV]
    A --> C[JSON]
    B --> D[Spreadsheet tools]
    C --> E[Web APIs]
````

---

## 1. CSV Files

CSV stands for **Comma-Separated Values**.

Example file:

```text
name,age
Alice,25
Bob,30

2. Reading CSV¶

Python provides the csv module.

import csv

with open("data.csv") as f:
    reader = csv.reader(f)

    for row in reader:
        print(row)

3. Writing CSV¶

import csv

with open("out.csv", "w") as f:
    writer = csv.writer(f)

    writer.writerow(["name", "age"])
    writer.writerow(["Alice", 25])

4. JSON Files¶

JSON (JavaScript Object Notation) is widely used for structured data.

Example JSON:

{
  "name": "Alice",
  "age": 25
}

5. Reading JSON¶

import json

with open("data.json") as f:
    data = json.load(f)

print(data)

6. Writing JSON¶

import json

data = {"name": "Alice", "age": 25}

with open("data.json", "w") as f:
    json.dump(data, f)

7. Summary¶

Key ideas:

• CSV represents tabular data
• JSON represents structured data
• Python provides csv and json modules
• these formats are widely used for data exchange