HTTP – Definition and meaning

What is HTTP?

HTTP (Hypertext Transfer Protocol) is a communication protocol used for transferring data on the World Wide Web. It forms the basis for most Internet applications and enables interaction between clients, which are typically web browsers, and servers that provide web pages and other resources.
In this guide, we will look at how HTTP works, various HTTP methods and security aspects of HTTP, particularly in relation to HTTPS (HTTP Secure).

How HTTP works

HTTP works according to the client-server model. A client, such as a web browser, sends a request to a web server, which sends back the requested data. This communication takes place in the form of requests and responses, which are exchanged in specific formats:

• HTTP request: A request to the server containing information about the requested resources and details of the request.
• HTTP response: A response from the server containing the status of the request and the requested data.

HTTP methods

There are various HTTP methods that a client can use to interact with a server. The best known are

• GET: This method requests data from the server without making any changes to the resources.
• POST: This method is used to send data to the server to create new resources or change existing ones.
• PUT: This method is used to replace or update a specific resource on the server.
• DELETE: This method deletes the specified resource on the server.

HTTP status codes

Each HTTP response contains a status code that indicates whether the request was successful or whether there was a problem. Some common status codes are:

• 200 OK: The request was successful.
• 404 Not Found: The requested resource could not be found.
• 500 Internal Server Error: There is a problem with the server.

HTTP vs. HTTPS

HTTP alone is not secure, which means that data transmitted via this protocol can be intercepted by third parties. This is why HTTPS (HTTP Secure) was introduced, a secure version of the protocol that uses SSL/TLS encryption to protect data in transit. The use of HTTPS is particularly important for websites that request sensitive information, such as online banking or e-commerce websites.

Advantages of HTTPS

• Secure data transmission through encryption.
• Protection against man-in-the-middle attacks.
• Improved SEO rankings, as search engines favour HTTPS websites.

Illustrative example on the topic: HTTP

Imagine you want to visit the website of an online shop. You enter the URL in your web browser, which acts as a client. Your browser sends an HTTP request to the online shop's server. The server processes the request, finds the page in question and sends back an HTTP response that shows you the content you wanted to see. If the shop website uses HTTPS, all communication between your browser and the server is encrypted. This means that nobody can intercept or manipulate your information as you navigate through the shop or enter personal data.

Conclusion

HTTP is at the heart of communication on the web. Through its various methods and status codes, it enables efficient and structured communication between clients and servers. The introduction of HTTPS has significantly improved the security of data transmission on the internet and should be prioritised by all website owners. If you would like to learn more about related topics such as APIs or web development, please also visit our encyclopaedia on APIs or web development.