What Happens When
A community written, deliberately exhaustive answer to "what happens when you type google.com into your browser and press enter?" It starts at the keyboard interrupt and works through DNS, ARP, sockets, the TLS handshake, HTTP, HTML parsing, CSS and rendering. Reading it once is a fast way to find the layers you use every day but could not explain. It has not been updated since 2024, so newer pieces such as HTTP/3 and QUIC are not covered.
GitHub repo
Web Development
Alex Gaynor
Intermediate
Free
A community written, deliberately exhaustive answer to "what happens when you type google.com into your browser and press enter?" It starts at the keyboard interrupt and works through DNS, ARP, sockets, the TLS handshake, HTTP, HTML parsing, CSS and rendering. Reading it once is a fast way to find the layers you use every day but could not explain. It has not been updated since 2024, so newer pieces such as HTTP/3 and QUIC are not covered.
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