Overview
Your complete guide to How the internet and networks work
From your device to a server on another continent: addresses, packets and ports, DNS, encryption and the journey of a link, then HTTP, the language of the web. The foundation you need before front ends and servers.
Non-technical and technical learners alike. Every part opens two ways in: a plain path built on an analogy for someone starting from zero, and a detailed path for someone who knows the basics and wants depth.
An animation, then what you need before you start, then the idea with code you run, then a worked example, then review cards and "test your understanding" questions.
Do not leave a part before you can answer its questions without guessing. Reading alone proves nothing.
Pick a topic
A look at How the internet and networks work
You build the picture bottom up: how packets travel, then how a name becomes an address and the road is secured, then the conversation itself between browser and server.
| Part | Topic | You learn |
|---|---|---|
| 1 | Networks and addresses: from your device to the world | IP addresses, packets and routers, ports, TCP and UDP |
| 2 | From link to page: DNS and the full journey | URL parts, DNS and caching, TLS, and rendering |
| 3 | HTTP: how browsers and servers talk | Requests and responses, verbs, status codes, headers and cookies |
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