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CGP Grey explains how traffic jams come from human driving behavior such as tailgating and reaction delays, and how leaving gaps and smoothing speed would reduce congestion. It also touches on self-driving cars.

A short video from the trafficwaves.org site showing how traffic jams and standing waves form, including the fight between cheaters and blockers at an exit-lane backup. It also touches on how individual driving behavior affects the flow.

Not Just Bikes explains how Dutch traffic lights use early detection, transit priority and conflict-free design to cut waiting. The aim is to move as many people as possible rather than as many cars.

Technology Connections explains how LED traffic lights, which do not melt snow, drew complaints and were blamed for accidents. He uses it to illustrate the 'but sometimes' fallacy against new technology.

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 short explainer on the history and mechanics of public key cryptography and the Diffie-Hellman key exchange. It uses a mixing-paint-colors analogy to show how two parties can agree on a shared secret in public.

Not Just Bikes explains the Downs-Thomson paradox using Amsterdam and Toronto: road widening doesn't fix congestion, and buses stuck in traffic make transit slow. It argues for giving transit its own priority infrastructure.

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.

A short Art of the Problem clip explaining Diffie-Hellman key exchange, using a paint mixing analogy for one-way functions and touching on modular arithmetic and discrete logarithms.

Not Just Bikes looks at traffic in the Bahamas to show that a small country can be just as car-centric as a big one. He ties it to land use, car dependence and how dedicated transit lanes help.

Minutephysics compares how efficiently different processes convert mass to energy per E=mc^2, from fire and fission to fusion, antimatter and black holes, which can convert a large fraction of mass to energy.

WIRED has UCLA professor Amit Sahai explain zero-knowledge proofs to a child, a teen, a college student, a grad student and an expert. Each round goes deeper into the cryptography and why it matters.

IBM's Dr. Talia Gershon explains quantum computing to five people of increasing expertise: a child, teen, college student, grad student and professional. The WIRED series format moves from simple analogies to technical detail.

Practical Engineering explains how canal locks work, including the water-saving basins of the new Panama Canal locks.

WIRED's 5 Levels format with Jacob Collier explaining harmony to a child, a teen, a college student, a professional and Herbie Hancock.

Real Engineering examines the efficiency of hydrogen as an energy carrier. It follows production, storage and fuel cell conversion losses and compares hydrogen cars with battery electric vehicles.

Technology Connections explains how refrigerator and freezer design affects energy use, using chest freezers to show why top-opening designs and layout choices matter. It includes thermal-camera footage of cold air spilling out of upright units.

Technology Connections explains why heat pumps matter right now, covering their efficiency, how they hold up in cold weather and the energy savings over burning fuel. It follows his earlier explainer on how they work.

Geekerwan reviews smartphone CPUs by power efficiency rather than benchmark scores, with test methodology and chapters on Qualcomm, Apple, Samsung and Google chips. It explains why high benchmark scores can coexist with heat and poor battery life.

Technology Connections explains how heat pumps work as reversed air conditioners and why they can deliver several times the heat of resistive heating per unit of energy. It also tackles common myths such as poor cold-weather performance.

A Technology Connections video on how ground-source (geothermal) heat pumps work and why they hold efficiency in winter. It also covers related heat pump information, and the description notes air-source heat pumps have since improved.

Technology Connections explains why electric kettles are uncommon in the US, centering on 120V circuits limiting power. He tests ways of boiling water on gas, electric ranges and kettles.

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.

Engineering Explained examines Toyota's hydrogen-burning V8 engine built with Yamaha and explains the practical problems of hydrogen combustion vehicles. It covers efficiency, storage and distribution issues.

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.

Technology Connections explains in 33 minutes why thermoelectric (Peltier) cooling is far less efficient than compressor-based refrigeration.

CityNerd Ray Delahanty explains induced demand and what happens when freeways are widened. He walks through the economics of supply and demand applied to traffic and asks how much new traffic appears and whether congestion returns.

CGP Grey compares airplane boarding methods, based on an arXiv paper, and shows why the intuitive back-to-front approach is slow while random or outside-in boarding does better.

Technology Connections' long closing video in his heat pump series, arguing that adopting heat pumps is well within reach. It explains how they work and what it takes to start using them.

Technology Connections looks at why awnings disappeared from houses and how effective they are at cutting solar heat gain and cooling costs. It argues they are a simple, forgotten cooling technology.

Real Engineering explains why biofuels, especially corn ethanol, are a poor energy source, looking at energy inputs, efficiency and carbon cost.

Technology Connections tests how quickly gas, induction and standard electric stoves boil water, with CO2 measurements and a discussion of the advantages and disadvantages of each.

Technology Connections examines why light bulbs have the lifespans they do, including the real history of the Phoebus cartel. He shows that bulb life trades off against brightness and efficiency rather than being simple planned obsolescence.

Not Just Bikes argues that stop signs are a poor traffic control, drawing on Dutch practice and the Idaho stop to show intersections can be safer without them, especially for cyclists.

Geekerwan's Chinese-language review of Intel's Lunar Lake lightweight laptop chip, covering performance, perf-per-watt curves and battery life benchmarks. It tests whether x86 can compete on efficiency.

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.

Wendover Productions explains why drone delivery has not become the future once promised. It covers no-fly zones, costs and the difficulty of the final drop-off.

Technology Connections' hour-long guide to electric vehicles, covering costs, trade-offs and especially how little home charging power most drivers need.

Sabine Hossenfelder explains why hydrogen is a poor answer for decarbonization, covering how most hydrogen comes from fossil fuels, the efficiency losses of green hydrogen and reliance on rare metals in fuel cells.

A two-minute explanation of what a rocket mass heater is, starting from how a conventional wood stove works and why creosote and chimney fires occur. It shows how burning hot and storing the heat in thermal mass makes for an efficient heater.