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How data actually moves between two machines — the lookup, the handshake, the encryption, and the limits that decide who gets through.
6 interactive explainers. Each one is a visual story with a live simulation and a knowledge check, and the Ask ViLearn tutor beside all three. Free, and nothing requires an account.
Every page you've ever visited began with the same quiet question: where is this, actually? Follow one DNS lookup through caches, root servers, and…
Beginner · 8 min · Story, simulation and quiz
Between your laptop and a server sits a chain of routers free to drop, delay or reorder anything they carry.
Beginner · 9 min · Story, simulation and quiz
Netflix can buy more servers and more disks. It cannot buy the link between your internet provider and the rest of the internet, and at 9pm there is not…
Intermediate · 12 min · Story, simulation and quiz
The connection TCP just opened is a postcard. Every router on the path can read it, and change it. One extra round trip turns it into a sealed envelope.
Intermediate · 10 min · Story, simulation and quiz
Sixty requests a minute sounds like a simple rule. It isn't. Send them spread out and they all get through.
Beginner · 9 min · Story, simulation and quiz
A normal web request is one question and one answer, and the server is never allowed to start.
Intermediate · 11 min · Story, simulation and quiz
Other categories: Deployment & Cloud · Databases & Search · Developer Tools · AI & Machine Learning · Systems
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