What is HTTP? Explain the steps that are involved for each request from a client to the server.

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# HTTP and Client-to-Server Request Steps

**HTTP (HyperText Transfer Protocol)** is an application-layer protocol used for communication between clients and web servers. It follows a request-response model.

## Steps
1. **Enter/request URL:** The browser determines the target resource.
2. **DNS resolution:** The domain name is resolved to an IP address when necessary.
3. **Connection:** The client establishes a connection to the server (typically TCP; HTTPS also establishes TLS security).
4. **HTTP request:** The browser sends a request containing a method such as `GET` or `POST`, URL/path, headers and possibly a body.
5. **Server processing:** The web server/application processes the request, possibly accessing files, code or databases.
6. **HTTP response:** The server returns a status code, headers and usually a response body.
7. **Browser processing:** The browser interprets the response and renders the page; it may make additional requests for CSS, JavaScript, images, etc.
8. **Connection reuse/close:** The connection may be reused or closed according to the protocol and headers.

### Example
```text
Browser → HTTP GET /index.html → Web Server
Browser ← HTTP 200 + HTML ← Web Server
```

**Common status codes:** `200 OK`, `404 Not Found`, `500 Internal Server Error`.

HTTP and Client-to-Server Request Steps

Steps

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