Two worlds that could not be more different live on the web. One is JavaScript, the language behind most of the sites you visit. The other is binaries: compiled programs that the browser executes dire...
It sounds like an exaggeration, but it is true: when you send a message to someone across the ocean, it most likely travels thousands of kilometres along the seabed. Communications satellites account ...
You open your favourite series in 4K and barely notice a detail bordering on the impossible: the video you are watching travels down your fibre at about 15–25 megabits per second (Mbps). Run the numbe...
Every time you write a line of code that creates an object, a list or a string of text, that data takes up RAM memory. At some point you stop using it, but the space it occupies is not freed by itself...
HTTP/3 is the third major version of the protocol that moves the web: the set of rules your browser and servers use to exchange pages, images and data. What you are reading right now has most likely t...
When a program runs, it behaves as if it had access to a seemingly unlimited, contiguous and stable amount of memory. In reality it lives inside an illusion carefully orchestrated by the operating sys...
Email is one of the few internet services that still works almost the same way it did forty years ago. Its base protocol, SMTP (Simple Mail Transfer Protocol), was defined in 1982 for a small network ...
When you open a website, every click is a letter: your browser asks for something, the server answers, and the exchange is closed. That is fine for reading an article, but what about a chat where the ...
When you press «pay» on a website, your request does not travel straight from the browser to the bank’s database. In almost every modern system, what happens in between is a long queue of messag...
When two or more people type on the same document at once, a very simple idea to state becomes a genuinely hard computing problem. This is not a minor design flaw but a real limit: two copies of the s...
When you ask a database for the row holding the order you placed three months ago, the answer usually arrives in a few milliseconds. Across a table with millions of rows, that is not magic: it is the ...
Every time you load a website with real traffic, an invisible component is deciding which server should receive your request. It is not magic and not a secret jury: it is the load balancer, the entry ...