witch

A 1951 Bell System training film showing how telephone calls are routed through a step-by-step (Strowger) switching office.

Matt Parker of Stand-up Maths examines scatter plots that were claimed to show fraudulent vote-switching in Michigan's 2020 election. He recreates the analysis and shows that the pattern arises from comparing percentages across different bases, not from fraud.

Technology Connections explains how old-fashioned non-electronic rice cookers work, using a magnet and spring switch tripped by the Curie point. It shows the thermodynamics and magnetism behind a simple appliance.

A PBS Space Time episode explaining how space and time swap roles inside a black hole's event horizon. It is part of the channel's black hole series.

Veritasium explains X-chromosome inactivation, where different cells in a woman's body switch off different X chromosomes, giving a mosaic pattern. It uses animation from the WEHI institute and connects to calico cat coloring.