When you type an ñ and a server in Tokyo receives it intact, a worldwide agreement is working in the background: the Unicode standard and its dominant encoding, UTF-8. It may look like magic, but it i...
Imagine you need to verify that a multi-gigabyte download arrived uncorrupted, or that your password is stored securely on a server, or that a document has not been tampered with. All three problems a...
There is a moment in the recent history of Linux when the kernel stopped being an untouchable monolith. Years ago, if you wanted to inspect or filter your server’s network traffic you had to acc...
At the dawn of computing, every program was responsible for returning to the system the memory it no longer needed. Forget to do it and the machine would run out of resources and eventually crash. Tha...
When you open a web page, your browser does not just render HTML: it runs JavaScript that requests data from other servers, from analytics to recommendations. Each of those requests crosses an invisib...
For decades, JavaScript was the only language able to run inside the browser. Everything else —Python, C++, Rust— was left out, doomed to run on a server. WebAssembly (short for wasm) broke that monop...
Every time you type something into a search engine, the answer arrives in a fraction of a second. That speed is no magic trick: it relies on work that happened long before you pressed Enter. By the ti...
The story of a thirty-year wait When you hit Enter, your request does not travel as a loose envelope across the internet. Before moving a single byte of useful data, your browser and the server have t...
You type a web address, press Enter and, in under a second, the page appears. Between those two moments the browser does not simply “show” a file: it runs one of the most complex operation...
When you send a photo on WhatsApp, you compress dozens of megabytes until they fit into just a few. When a web server serves you a page, it shrinks it with Brotli before sending it over the network. C...
When you save a file and hit “save”, almost nobody thinks about what happens inside the disk. The reality is stranger than the folder icon suggests: your file is not stored as one continuo...
When you send a message through a messaging app, the temptation is to think that “encryption” protects everything. But there is a huge difference between encryption in transit and end-to-e...