basic training

3Blue1Brown's first chapter on deep learning explains what neurons and layers are and the math underlying a basic neural network, using handwritten digit recognition with visual animations.

Ted Nelson explains the original Xanadu hypertext idea of visible connection, the notion that links between documents should be shown and preserved. He argues that the Web and current document standards lost this concept.

Rick Beato argues that adults cannot develop true perfect pitch, which he ties to critical-period brain plasticity and language acquisition. He says it can only be developed in young children, and discusses the research behind this.

Robert Miles explains reward modelling, in which an AI learns what humans want from their preference comparisons instead of a hand-written reward function. He walks through the 2017 paper on deep reinforcement learning from human preferences.

FortNine's tongue-in-cheek guide to why drivers fail to see motorcyclists and how riders can make themselves more visible. It touches on perception psychology, including the role of saccades.

A two-minute animated introduction to Bitcoin from 2011, explaining it as a peer-to-peer digital currency. It was widely shared in Bitcoin's early days as the standard newcomer explainer.

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.

An animated visualization of basic quantum mechanics using a free particle, with simulations based on the actual equations. It covers waves, particles, and how measurement collapses the wavefunction.

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.

3Blue1Brown's second neural network chapter explains cost functions and gradient descent, showing how a network learns by minimizing error during training.

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.

ScienceClic explains why nothing can go faster than light by treating motion through space and time together, so everything moves at the speed of light through spacetime. It uses animated visuals to cover relativity basics in 12 minutes.

3Blue1Brown, in collaboration with minutephysics, introduces the math of superposition and quantum states using polarized light. It builds up the quantum behavior of photons as a simple counting and probability problem.

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

A SAAMI-produced training video for firefighters explaining what happens when sporting ammunition burns, including that unchambered cartridges lack the energy to penetrate much. It includes test footage of ammunition in fires.