Steps in HTTP process

There are a few steps in HTTP process. I will try to explain these steps.

1. Selection of the protocol to use. A URL may start with HTTP or HTTPS. S in it name stands for word - "secure". Securing information is done via encrypting it. I will explain more about HTTPS encryption later.

2. Second step in this process is to lookup IP address to which connect. IP address can be resolved via querying DNS (Domain Name Server) for that information.

3. A browser (or web application) sends request to access this page.

4. This web server sends back the response. This response includes two parts. First one is HTTP header, and second one is content. HTTP header includes status and sometimes additional information needed for the response.

Typical response status codes are: 200 - normal response, 301 - permanent redirect, 302 - temporary redirect, 403 - request was normal, however server refused to display this information, 404 - error occurred finding requested content, error 500 means that request was accepted by the web server, however there was processing error.

5. If there was no error on server end, then content of that web page will be returned by the web server and rendered by the web browser.

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