HTTP Requests and Responses
The interaction between web browsers and servers is a fascinating journey of requests and responses. Here's how it unfolds:
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User Request: Upon entering a URL or clicking on a link, you're making a request to a web server, typically known as an HTTP request.
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DNS Lookup: Before reaching the server, the domain name in the URL gets translated into an IP address by the Domain Name System (DNS).
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HTTP Request: With the IP address known, your browser sends an HTTP request to the web server. This request includes the method (e.g., GET for retrieving data, POST for sending data), the URL, and other information like headers which can include details about the browser, requested language, and more.
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Server Processing: The server receives the HTTP request, processes it, and generates an appropriate response. This may involve querying databases, rendering HTML pages, or other server-side operations.
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HTTP Response: The server sends an HTTP response back to the browser, containing the status of the request (like 200 for success, 404 for not found), headers with metadata, and the actual content, like HTML, images, or videos.
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Browser Rendering: Upon receiving the HTTP response, and if the request was successful, your browser renders the content on the screen. It parses the HTML, CSS, and JavaScript to build the visual representation of the page.
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Additional Requests: The initial HTML may reference other resources like images, stylesheets, or JavaScript files. For each of these, the browser makes additional HTTP requests, and the server sends back HTTP responses.
As you interact with the web page, like submitting forms or loading new content, this cycle of requests and responses between the client and server continues, enabling the pulsing heart of web functionality.