hank johnson

A short animated explainer that stages a $100 footrace in which contestants start at different distances from the line, depending on the advantages or disadvantages they inherited. It uses the race as a metaphor for how unequal starting points shape outcomes, citing US census income and poverty figures.

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.

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.

An episode of Journey to the Microcosmos, hosted by Hank Green, about diatoms, single-celled algae with glass shells. It covers their role in producing a large share of Earth's oxygen and their uses in beer filtering, paint and kitty litter.

Tom Scott explains phatic expressions such as hello, thank you and how are you, which carry social meaning rather than information, and why replies like no problem can seem rude to some people.