HTTP (Hypertext Transfer Protocol) is the foundation of data communication for the World Wide Web. It functions as a request-response protocol in the client-server computing model. A web browser, for example, may be the client and an application running on a computer hosting a website may be the server.
Request Methods (Verbs)
- GET: Requests data from a specified resource (e.g., loading a webpage).
- POST: Submits data to be processed to a specified resource (e.g., submitting a form).
- PUT: Updates a specified resource.
- DELETE: Deletes the specified resource.
Status Codes
- 200 OK: Success.
- 301 Moved Permanently: The page has moved to a new URL.
- 404 Not Found: The server cannot find the requested resource.
- 500 Internal Server Error: The server crashed or encountered an error.
Frequently Asked Questions
1. What is the difference between HTTP and HTTPS? The ‘S’ stands for Secure. HTTPS encrypts the data transferred between the client and server using TLS/SSL certificates, protecting sensitive info like passwords and credit cards.
2. Why do I see a 404 error? It means the link you clicked is broken, the page was deleted, or you typed the URL incorrectly.
3. Is HTTP stateless? Yes. The server does not keep any data (state) between two requests. This is why we use “Cookies” to remember user logins and shopping carts.
4. What is a URL parameter?
It is the part of a URL that follows a question mark (e.g., ?search=shoes). It sends extra information to the server via a GET request.
5. What is a User-Agent? A string of text sent by your browser to the server identifying the browser type, operating system, and device. Servers use this to serve mobile or desktop versions of a site.