What happens when I open a website?

The canonical interview question, taken seriously: from the URL bar through DNS, TCP or QUIC, TLS and HTTP, across routers to a load balancer and a backend — and at the deepest level, through both kernels. Zoom in until nothing is magic.

Inputhttps://engineer-atlas.dev/dsaWhat actually happens between pressing Enter and pixels on the screen?
ZoomThe story most people tell: the browser asks "the internet", a server answers. Correct, and useless for debugging. Every arrow here hides a layer.
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Click a node to see what happens there, what state changes, how it fails, and which lesson explains it. Then zoom to the next level and watch the arrow you clicked expand into its own chain — no step is magic.

Continue with the lessons

What Happens When You Press EnterFollowing One Lookup Through Every CacheThe Three-Way HandshakeThe TLS HandshakeThe Lifecycle of One HTTP RequestFollow send() Through the OS to recv()