Tech myths that won't die: 404, 640K, the space pen and Nuclear Gandhi
Room 404 at CERN, Bill Gates's 640K quote, NASA's million-dollar space pen, the Gandhi bug in Civilization, Grace Hopper finding the first bug. They're great stories, and most...
Quizzes
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The CSS rendering pipeline: reflow vs repaint & why transform is cheap
Follow a pixel from CSS to screen: Style → Layout → Paint → Composite. See exactly what makes the browser re-run Layout (reflow) versus just Paint (repaint), why transform and...
The internet runs on cats: what the research says
Cats are the internet's unofficial mascot, and the programmer with a cat on the desk is a stereotype. But do tech people really prefer cats? Along the way you'll meet the...
The IT Crowd: have you tried turning it off and on again?
The IT Crowd ran for four series on Channel 4 and gave every help desk its motto. Start with the characters, the running jokes and the awards. Then find out why turning it off...
The Node.js event loop: libuv phases, timers & nextTick
Step through the server-side event loop, the one libuv runs — not the browser model. Walk the phase cycle (timers, pending callbacks, poll, check, close), then settle the...
TypeScript generics, inference & type-level programming
Two clusters in one quiz: Generics & Inference (when TS infers vs. when you must annotate, extends constraints, defaults, and why an unconstrained <T> leaks unknown) and...
TypeScript type system: deep cuts
Narrowing you can trust, the any/unknown/never/void lattice, structural-typing surprises, and literal widening with as const & satisfies. Every explanation compiles the snippet...
Undo, redo, and back: stacks and queues in the UI
LIFO and FIFO made concrete in the interfaces you build every day: undo/redo as two mirrored stacks, the classic bug where a fresh edit must clear the redo stack, the browser's...
Units & measurement trivia: light-years, the metric system, and classic misconceptions
Sixty-four questions on the units we measure the world with — and the famous mistakes people make about them. Six parts: cosmic distances (why a light-year is a distance and...
WCAG 2.2 visual checks: contrast, focus, target size & reading order
Each Question shows a screen with an accessibility problem you can spot by eye. The Explanation then shows the same screen as an accessibility tree, so you can compare what...
WebRTC data channels vs WebSockets: P2P, SCTP & configurable reliability
When real-time delivery goes peer-to-peer: how WebRTC data channels differ from WebSockets — SCTP-over-DTLS-over-UDP transport, configurable reliability and ordering, signaling...
WebSocket frames: opcodes, masking & close codes
Below the handshake lies the WebSocket wire format (RFC 6455): the frame header, opcodes, mandatory client masking and why it exists, payload-length encoding, fragmentation,...