type checkers

Professor Brailsford of the University of Nottingham describes how the university set out to print its own mathematics exam papers in the 1980s. The story centers on getting a Mergenthaler Linotron 202 typesetter to work with their own software.

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.

Matt Parker talks Numberphile through the different kinds of numbers: algebraic, transcendental, computable, normal, and beyond. It shows how few numbers we can actually name or describe.

A three-minute excerpt from Milton Friedman's Free to Choose in which he uses a pencil to show that no single person knows how to make it. He argues that the free market coordinates countless strangers peacefully.

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.

Everyday Astronaut's Tim Dodd runs an hour-long, data-driven analysis of what rockets actually emit and how that compares with airliners and other industries. It breaks down exhaust by propellant type, per-passenger and total emissions, and ways launches could be cleaner.

Everyday Astronaut explains the basic physics of rocket engines, the main engine cycles and fuel types, then compares SpaceX's methane-fueled full-flow staged combustion Raptor to other engines. It runs nearly 50 minutes with chapter markers.

Technology Connections explains why humidity matters and compares the main types of humidifiers, including evaporative and ultrasonic designs. It covers how and why you would add moisture to indoor air.

Numberphile's James Grime introduces quaternions, a type of number beyond the complex numbers, building up from real and complex numbers and explaining why they are useful.

Aaron Francis walks through how PHP has changed from 2012 to 2023, covering traits, array destructuring, generators, typed properties and more. It is a quick chaptered tour of modern PHP features.

ACS Reactions investigates why Mexican Coke, supposedly cane sugar sweetened, tested as having glucose and fructose, explaining that sucrose breaks down in acidic soda.

Veritasium visits the US Navy's Crane facility to test top night vision goggles. It explains how image intensifier tubes and thermal or digital systems work and compares the generations of the technology.

Wendover Productions explains why American towns, retail and buildings increasingly look alike, covering zoning pressures, corporate standardization and cheap construction types like 5-over-1 buildings.