1. What is a Cookie?

• A cookie is a small piece of data stored by the browser.
• Set by the server → sent to the client → stored → sent back with every request.
• Used for:
  • Session management (login tokens, shopping carts).
  • Personalization (language, theme).
  • Tracking (analytics, ads).

📌 Example:

HTTP Response:
Set-Cookie: session=abc123; Path=/; Secure; HttpOnly; SameSite=Strict

Next Request:
Cookie: session=abc123

2. Important Cookie Attributes (Flags)

🔹 HttpOnly

• Prevents JavaScript from accessing the cookie (document.cookie).
• Protects against XSS stealing session cookies.

✅ Example:

Set-Cookie: session=abc123; HttpOnly

👉 Now JS can’t steal it using alert(document.cookie).

🔹 Secure

• Cookie is only sent over HTTPS (not plain HTTP).
• Protects against MITM attacks where cookies might leak in plaintext.

✅ Example: