knowledge work

An 8-minute explainer on the Lightning Network and how it relates to Segwit, Bitcoin and Litecoin. It covers how off-chain payment channels route payments to scale blockchain transactions.

3Blue1Brown's first chapter on deep learning explains what neurons and layers are and the math underlying a basic neural network, using handwritten digit recognition with visual animations.

Linus Tech Tips reviews the first Framework Laptop, a fully repairable and upgradeable machine. The reviewer expected a flimsy chunky device and was happily surprised.

Two Minute Papers covers a paper on speeding up fluid and smoke simulation with convolutional networks. It contrasts the approach with earlier regression forest methods.

CGP Grey argues that your brain treats a whole home as one room during lockdown, blurring work, rest and leisure. He recommends creating separate spaces and routines for different activities to stay balanced.

A 1936 Chevrolet-sponsored film that explains how a car transmission works by treating gears as spinning levers. It uses physical models to make the mechanism clear.

Jared Owen's 3D animated breakdown of how a Brunswick GS-X bowling pinsetter works, showing its mechanisms for sweeping, lifting and resetting pins and balls.

A Kurzgesagt animation giving a big-picture tour of the human immune system, its organs, transport network, and the cells it produces every day. It accompanies their IMMUNE book.

Illumina's 3D animation of its sequencing-by-synthesis workflow, from sample preparation and cluster generation to sequencing on a flow cell and data analysis.

Sabine Hossenfelder explains how the greenhouse effect actually works, given that infrared is mostly absorbed low in the atmosphere already. She walks through why more CO2 still warms the surface.

Ben Eater gives a detailed look at how an NPN bipolar junction transistor works and what it does. It is an eleven-minute explanation aimed at building real understanding of the device.

Wendover Productions explains how overnight shipping works, covering the hub-and-spoke logistics of companies like FedEx and UPS and the use of cargo aircraft. It touches on the economics that make next-day delivery possible.

Ben Felix explains how central bank money creation and quantitative easing actually work, and what they do and do not imply for asset prices and currency. He addresses the common belief that the Fed prints unlimited money and props up markets.

An RSA Animate drawing of Barbara Ehrenreich's talk on the darker side of positive thinking. It argues that forced positivity in culture, work and policy can be harmful and played a part in the financial crisis.

The 8-Bit Guy explains the color limitations of 1980s computers and consoles such as the NES and Commodore 64. It shows how sprites, attributes and palettes shaped the look of old games.

Mark Handley of UCL explains, with simulation visualizations, how early Starlink satellites without inter-satellite links could still give low-latency wide-area communication by hopping via ground relays. He shows it can beat fibre on many long paths.

Technology Connections explains the early history of analog color television, from the 1954 start of modern color broadcasting, and how shadow masks work in CRTs. It is the first in a series on how analog color TV works.

The Slow Mo Guys film a TV and screens with a high-speed camera to show how displays build an image. The footage includes CRT-style scanning and how pixels light up over time.

Applied Science explains how retail anti-theft tags work. A tiny magnetostrictive strip acts as a mechanical oscillator excited by a magnetic field, and magnetizing or demagnetizing it arms or disarms the tag.

Technology Connections explains how analog television produced moving images without computers, covering scanning, CRTs and standards like NTSC and PAL. It is part of a series on analog TV.

A 1937 GM-produced film explaining how the automobile differential lets wheels turn at different speeds around a corner. It uses clear animations and cutaway demonstrations to build the idea from first principles.

An RSA Animate whiteboard adaptation of Dan Pink's talk on what motivates people at work. It argues that beyond simple tasks, autonomy, mastery and purpose drive performance more than money.

Veritasium explains magnetism as a consequence of special relativity. Length contraction of moving charges makes a current in a wire attract or repel a nearby moving charge.

Veritasium explains why bicycles are stable, arguing that gyroscopic effects are not the answer. The video shows countersteering and an experiment where riders blocked from steering the opposite way cannot turn.

Wes Bos breaks down the techniques behind the McMaster-Carr website's speed: server-rendered HTML, prefetching, CDN and service worker caching, preloading, critical CSS and fixed-size images. He also notes its old-school jQuery and YUI JavaScript.

3Blue1Brown's third deep learning chapter gives a visual, intuitive account of backpropagation and what happens to a neural network as it learns. A follow-up video covers the underlying calculus.

Mark Handley of UCL looks at how SpaceX's November 2018 revisions to the Starlink constellation affect network behavior. The video visualizes the orbits and routing and estimates latencies, building on his earlier video and research paper.

A short cartoon explaining how language models like ChatGPT work, from autocomplete and conditional probabilities to neural networks, gradient descent and backpropagation. It shows how networks act as universal function approximators.

A Wendover Productions explainer on how budget airlines can sell tickets for under 10 euros. It covers the costs airlines face and how low-cost carriers structure their business.

Rob Miles explains for Computerphile why simple rule sets like Asimov's Three Laws cannot make robots and AI safe. Terms like harm and human are too ambiguous to specify precisely.

3Blue1Brown's chapter 4 on deep learning gives a more formal, symbol-based account of backpropagation calculus, connecting the intuition from the previous chapter to the math found in textbooks and code.

Harvard professor Arthur Brooks explains why boredom is useful rather than something to avoid. He describes how a wandering mind engages the brain's default mode network, which supports creativity and curiosity, and suggests it may protect against depression.

Short Curious Droid video on why NASA could not simply rebuild the Saturn V's Rocketdyne F-1 engine for the SLS boosters. It explains that the engines were hand-tailored and that much of the know-how was never documented, so the blueprints were not enough.

Tom Scott visits an eHighway test in Lubeck, Germany, where electric trucks with pantographs draw power from overhead wires. He explains how this could electrify road freight.

Real Engineering explains how Zipline built a drone delivery network for medical supplies in Rwanda. It covers the fixed-wing drones, catapult launch, parachute drop and the logistics behind the service.

A Blender-animated explanation of the Toyota Hybrid Synergy Drive, showing how the engine, two motor-generators, planetary gearset and battery work together as an eCVT.

PBS Infinite Series explains how Shor's algorithm lets a quantum computer break RSA encryption, building on earlier episodes about cryptography and the math of quantum computers. It works through the idea step by step.

An RSA Animate illustrating a lecture by psychologist Philip Zimbardo on how people's perspectives on time (past, present, future) shape work, health and well-being.

Technology Connections explains how automatic windshield wiper rain sensors work, using an infrared light source and total internal reflection in the glass.

A US Chemical Safety Board video explaining how sugar dust explosions at the Imperial Sugar plant in Georgia killed fourteen workers in 2008.