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Linguist Geoff Lindsey explores vocal fry: what it is, who uses it, how it relates to glottal stops and accents, and why some people dislike it.

Technology Connections takes apart the step-by-step electromechanical logic of a 1970s pinball machine. He shows how relays, steppers and switches track state and score without electronics.

Casey Neistat's short New York Times op-doc investigating how accurate restaurant and packaged-food calorie labels really are. He gets items from chains like Chipotle, Starbucks and Subway measured by nutrition researchers and compares them to the printed numbers.

Practical Engineering explains Mechanically Stabilized Earth, where layers of reinforcement make soil strong enough to hold heavy loads, shown with a sand structure supporting a car. It notes that MSE walls are everywhere in infrastructure.

A video essay from the Alt-Right Playbook series that explains how extremist movements draw ordinary people in, using deniable rhetoric, bad-faith games, and gradual escalation. It draws on books about the alt-right, male radicalization, and cult-style brainwashing.

Technology Connections explains weaknesses in the US electrical system, centering on how cord and circuit ratings can mismatch and cause fires. It covers extension cords, power strips and plug history in about 25 minutes.

Huygens Optics explains the Fourier transform and shows how a lens performs one optically. A DLP projector is used as a Fourier filter to do simple pattern recognition on lithographic character patterns.

Robert Miles examines whether the case for AI safety is a Pascal's mugging, a tiny probability of an enormous payoff. He argues it is not, because AI risk does not depend on vanishingly small probabilities.

Not Just Bikes shows how traffic calming is built into streets across the Netherlands, from city centres to villages. Street design naturally slows cars and makes roads safer.

Technology Connections explains that US household power is split-phase, with two 120V legs that combine to 240V for large appliances. It covers the breaker panel and how the system works.

Cliff Stoll shows and explains his two Friden EC-132 electronic calculators for Numberphile. The video covers how these early machines worked, including their unusual acoustic delay line memory.

Curious Droid surveys vertical take-off and landing rockets that predate SpaceX and Blue Origin, including the McDonnell Douglas DC-X of the 1990s. It shows that propulsive landing has about 60 years of history.

Technology Connections takes apart a 1940s Sunbeam Radiant Control toaster. It senses the toast's own browning and lowers and raises it automatically using purely mechanical parts and no electronics.

The first of four short videos from Bill Hammack (engineerguy) introducing and giving the history of a 100-year-old mechanical computer, Michelson's harmonic analyzer. The series goes on to explain Fourier synthesis, analysis and operation of the machine.

A visual scale comparison of stars and cosmic objects, from planets up to some of the largest known stars, set to music. It is meant to convey the vastness of the universe.

3Blue1Brown explains why positive results on accurate medical tests are often false positives, and reframes Bayes' rule using likelihood ratios (Bayes factors) to update odds. It uses visual examples to make the reasoning intuitive.

Real Engineering looks at the numbers for running California on renewables, focusing on the large energy storage needed. It argues about the cost of batteries and the role of other sources.

Kurzgesagt explains the Holocene or Human Era calendar, which adds 10,000 years to the current year to anchor dates to the start of human civilization. It argues this gives a more sensible frame for human history.

Veritasium explains why many real-world systems follow power laws rather than normal distributions. It covers self-organized criticality, with simulations of sandpiles, magnetism and forest fires.

A SciShow episode in which Hank Green introduces five of the most dangerous chemicals, from lethal toxins to substances that explode on contact. It is an entertaining overview of extreme chemical hazards.

Historia Civilis tells the story of 46 BCE, the 445-day year in which Julius Caesar reformed the Roman calendar. It covers the political context, including the civil war, Cato and Cicero.

CodeParade's short devlog on how spherical geometry looks in 2D and 3D and why it feels so unusual, part of the Hyperbolica series on a non-Euclidean game.

A Welch Labs explainer on neural scaling laws and the compute-efficient frontier, asking why model loss seems to hit a line it cannot cross. It draws an analogy to an ideal gas law for AI.

A doctor from Medlife Crisis explains in under three minutes why even a rich patient should not simply order every medical test, touching on pre-test probability and Bayesian reasoning. False positives make blanket testing counterproductive.

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.

Steve Mould shows Spintronics, a set of mechanical components such as resistors, capacitors and transistors linked by chains, that give an intuitive feel for how electrical circuits work.

Practical Engineering's explanation of the February 2021 Texas winter storm and the resulting power grid outage. It lays out the facts about ERCOT, the grid's isolation, and how generation across fuel types failed in the cold.

CGP Grey's animated adaptation of The Dictator's Handbook, explaining how rulers stay in power by keeping a small group of key supporters happy rather than ruling fairly. It lays out selectorate theory and how resources shape regimes.

Technology Connections takes a long, detailed look at how a 1970s electromechanical pinball machine works, from relays to stepper motors and mechanical logic. It is the first part of a series.

Bill Hammack of engineerguy uses slow motion video to show how the IBM Selectric typewriter works. He focuses on its fully mechanical digital-to-analog converter, which turns key presses into rotation of the type ball.

Ward Cunningham explains the history and intent of the debt metaphor, which he coined while refactoring the WyCash product. He says debt means code reflecting an incomplete understanding of the problem, not sloppy programming.

Breaking Taps explains how the cryogenic mirror actuators on the James Webb Space Telescope achieve nanometer precision using flexures. It shows a 3D-printed replica and how one motor handles both coarse and fine motion.

A short RepresentUs explainer on how money corrupts American politics and what an anti-corruption act could do about it. It covers lobbying, super PACs and campaign finance, and pitches the group's proposed reforms. The video was later superseded by an updated version.

Numberphile explains the long and short scales for naming large numbers, covering millions, billions, trillions, milliards and the Greek myriad, with James Grime and Tony Padilla.

Matt Parker of Stand-up Maths examines the Texas Supreme Court filing claiming Biden's 2020 win had a one-in-a-quadrillion chance. He walks through why the statistical argument is flawed.

Practical Engineering gives a short introduction to concrete, covering the difference between concrete and cement, the ingredients, and reinforcement. It includes a hydraulic press demonstration of compressive strength.

Practical Engineering explains what a 100-year flood actually means, combining statistics, hydrology and how society treats risk. Grady walks through local drainage infrastructure and the caveats in estimating flood probability.

Practical Engineering explains why San Francisco's Millennium Tower is sinking and tilting, covering how geology and foundation design (friction piles in the Colma Formation) affect skyscrapers. It also covers the fix being attempted.

Practical Engineering explains how engineers and agencies put a dollar value on a human life to weigh cost against safety. It covers the legal and regulatory basis for these calculations.

VFX supervisor Jonas Ussing examines what studios mean by "no CGI", showing how much invisible CGI hides behind practical-effects marketing. It is the first part of a multi-part series that includes analysis of doctored behind-the-scenes footage.