What Exactly Is Sent When You Visit a Website?

Analogy:

Imagine you're ordering food online. You fill out a form with your name, address, and order. That form gets sent to the restaurant. The restaurant cooks your food and sends it back with a receipt. In web terms, you're the browser (client), the restaurant is the server, and the form is your HTTP request. Let's break down what that “form” actually contains.

Step 1: You Make a Request

Whenever you visit a webpage or interact with a web app, your browser initiates an HTTP request to the server.

What’s included in the request:

1. Request Line

   • Specifies the HTTP method (e.g., GET, POST), the path (e.g., /login), and the HTTP version.

   • Example:
     GET /dashboard HTTP/1.1

2. HTTP Headers

   • Metadata that describes the request and the client making it:

     • Host: Target domain (example.com)

     • User-Agent: Info about the browser or client

     • Accept: Data formats it can process (e.g., application/json)

     • Authorization: API tokens, Bearer tokens, Basic Auth, etc.

     • Referer, Origin, Accept-Language, and others

3. Cookies (if applicable)

   • The browser includes any cookies previously set by the server.

   • Example:
     Cookie: session_id=abc123; theme=dark

4. Query Parameters

   • Key-value data sent in the URL itself.

   • Example:
     /search?q=networking&sort=latest

5. Request Body (mainly in POST, PUT, PATCH)

   • Sent when data is being submitted (like login credentials or form data).

   • Often formatted in JSON or x-www-form-urlencoded.

   • Example:

       {
         "username": "admin",
         "password": "hunter2"
       }
     

6. IP Address & Port

   • Although not in the request body, the server sees your public IP and the source port as part of the underlying TCP connection.

---

How Is It Sent?

The request is sent over:

• HTTP: Plain text (not secure)

• HTTPS: Encrypted via TLS/SSL (secure)

The browser performs a DNS lookup, opens a TCP connection (or reuses one), performs a TLS handshake (if HTTPS), and then sends the full HTTP request over this connection.

---

Step 2: Server Processes the Request

• The server receives the request and uses:

  • The path to route to the correct resource

  • The headers and body to understand what you want

  • The cookies or tokens to identify you (session, auth)

• The server runs any business logic (e.g., checking credentials, fetching data, writing to a database)

---

Step 3: Server Sends a Response

The server crafts an HTTP response and sends it back to the client.

What’s in the response:

1. Status Line

   • Indicates the outcome of the request.

   • Example:
     HTTP/1.1 200 OK

2. Response Headers

   • Information about the response or instructions for the client.

     • Content-Type: Format of the response body (e.g., application/json, text/html)

     • Set-Cookie: Tells the browser to store or update a cookie

     • Cache-Control, Content-Length, Server, CORS headers, etc.

3. Response Body

   • The actual content: could be HTML, JSON, an image, or anything else.

   • Example (JSON):

       {
         "message": "Login successful",
         "user": {
           "id": 123,
           "role": "admin"
         }
       }
     

---

Summary of the Flow

1. Client sends request:

   • Includes method, URL, headers, cookies, and optionally body data.

2. Server processes request:

   • Validates input, applies logic, fetches/stores data.

3. Server responds:

   • Sends back a status, headers, and content.

4. Client receives response:

   • The browser renders it or processes the data (e.g., shows a success message or displays a page).

And remember:
If your date doesn't respond, it's not ghosting — it's just a 408 Request Timeout. 💔