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Veritasium explains why the kilogram is being redefined in terms of Planck's constant rather than a physical metal artifact. It visits NIST to show the Kibble balance and why measuring mass precisely is hard.

Technology Connections explains why single-hose portable air conditioners are inefficient and often a poor choice compared with window units. It details how the single hose pulls in warm outside air and wastes energy.

Ray Dalio's 30-minute animated video explains how the economy works through credit, debt, interest rates, and short- and long-term cycles. It is based on his template for understanding the economy.

Robert Miles explains instrumental convergence: why an AGI with almost any goal would tend to pursue sub-goals like self-preservation and resource acquisition. It builds on Omohundro's basic AI drives and his orthogonality thesis video.

Dave Jones of EEVblog looks at a sub-3-cent microcontroller from Padauk and other obscure Chinese manufacturers. He shows how to find such parts and where to buy them in stock.

A three-minute animated video that explains sexual consent through the analogy of offering someone a cup of tea. It is based on a blog post by Emmeline May.

Practical Engineering compares modern concrete with that of the Roman Empire, covering modern techniques like roller compacted concrete and water-reducing admixtures. It explains the tradeoffs of Roman construction versus reinforced concrete.

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.

Real Engineering looks at why nuclear power plants are expensive and how their economics compare with fossil and renewable alternatives. It is based on a video from the Illinois Energy Professors.

Asianometry explains why India, a chip design powerhouse, cannot fabricate chips, tracing the 1980s government attempt to build a national semiconductor champion and how it collapsed. It includes the sabotage at the SCL fab.

A short animation from Thames Valley Police that explains sexual consent by comparing it to offering someone a cup of tea.

Wendover Productions explains why Boeing's efficient 787 beat Airbus's giant A380, contrasting hub-and-spoke with point-to-point routes. It covers the economics of long-haul flights.

Asianometry traces the 30-year rise and peak of Japan's semiconductor industry from the 1950s to the 1980s, covering how a postwar country gained competence in an emerging technology.

An Economics Explained video arguing that the Netherlands shows taxes alone can't reduce wealth inequality. It distinguishes income inequality from wealth inequality and discusses the Gini index.

Potholer54 presents the climate science case and a market-oriented, conservative-friendly approach to addressing global warming, with sources listed. It is part one of a two-part series.

Veritasium explains the effort to redefine the kilogram, which was still defined by a physical artifact, and how a near-perfect silicon sphere from the Avogadro project helps. It also covers the history of the unit's odd naming.

Smarter Every Day shares a binaural audio recording of the SpaceX Falcon Heavy launch made by Trevor Mahlmann, with explanations of the sounds including the sonic booms of the landing boosters. It is meant to be heard with headphones.

Veritasium explores why energy is not conserved in general relativity, using Emmy Noether's theorem linking symmetries to conservation laws. Physicists interviewed explain energy loss in an expanding universe.

Yuta explains what Japan's 99% conviction rate actually means, noting that prosecutors drop cases unless confidence is very high. He argues that the number is widely misunderstood and cites his sources.

Historia Civilis explains the constitution of ancient Athens, including its assembly, offices and use of sortition to choose leaders. It draws on Aristotle and Plutarch.

Anders Puck Nielsen clears up common misunderstandings about what legally counts as genocide, then compares the situation in Gaza with the genocide case against Putin. The chapters cover the definition, individual intent, and the two case comparisons.

An Extra Credits episode on how games use Skinner box operant conditioning and reward schedules to keep players playing and spending. It argues for more immersive design mechanics than simple reward loops.

PBS Space Time considers whether life could be based on silicon instead of carbon, comparing the two elements' chemistry and why silicon is the most plausible alternative.

An Extra Credits episode on how MMO economies get overrun by inflation when players can mint unlimited gold by killing monsters. It covers approaches borrowed from real-world economics, such as anchoring or pegging currency, as alternatives to simple gold sinks.

Andreas Antonopoulos answers a Bitcoin Q&A question about energy consumption in mining. He argues that mining is arbitrage for the cheapest electricity, drives investment in renewables, and that the traditional financial system has hidden externalities.

CityNerd explains why traffic congestion grows nonlinearly as more cars use a road network, and why adding road capacity tends not to fix it. It covers the consequences for drivers, bus riders, cyclists and pedestrians, and discusses alternatives such as true bus rapid transit.

A long Technology Connections video arguing that public understanding of renewable energy is distorted. It covers solar economics, land use compared with ethanol corn, and battery myths such as cobalt.

Freya Holmer's 74-minute video essay on splines, covering Bezier curves, B-splines, derivatives and the different levels of continuity (C0, C1, C2), built with custom animation tools. She notes she did not cover non-uniform splines.

Tom Scott's long explainer on YouTube's copyright system, Content ID and the DMCA. He argues the platform's system is a workaround for a broader copyright system that does not fit the modern world.

A rap battle in which John Maynard Keynes and F. A. Hayek debate the causes of boom and bust, stimulus, and bailouts. It was produced by Econstories to teach the two schools of thought.

Wendover Productions explains how airlines make money from different cabin classes and why premium seats matter so much to profits. It also touches on how this shaped decisions such as the decline of supersonic travel.

3Blue1Brown visualizes the Riemann zeta function and the analytic continuation that extends it beyond where its series converges, building toward the Riemann hypothesis.

A short Not Just Bikes video on continuous sidewalks in the Netherlands, where the sidewalk runs unbroken across side streets so cars must visibly cross pedestrian space. It places them within Dutch sustainable safety and Vision Zero efforts.

Wendover Productions explains why modern airliners fly no faster than they did decades ago, covering the economics of speed and fuel efficiency, and why supersonic travel faded.

Mathologer uses continued fractions to show why the golden ratio is the most irrational number, comparing it with root 2, e and pi and pointing to where this shows up in nature.

Historia Civilis explains the origins and governing system of the Iroquois (Haudenosaunee) Confederacy. It covers the Great Law and the league's surprisingly intricate legal and political structure.

Robert Miles introduces the first of several videos on the paper 'Concrete Problems in AI Safety', focusing on how AI systems can cause accidental negative side effects. It explains the problem in accessible terms.

PBS Space Time examines Roger Penrose's idea that consciousness arises from quantum processes in the brain, and reviews new evidence about microtubules. It ends with an estimate of what replicating consciousness would demand.

Tom Scott explains Gricean maxims, the unwritten guidelines that shape how we understand each other. He uses examples such as why 'asbestos-free cereal' sounds suspicious.

A Kurzgesagt animated explainer on the climate and environmental cost of meat. It covers how beef drives deforestation and emissions, and how this compares with plant-based foods.