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A 1930s Chevrolet training film explaining the principles and development of the differential gear. It builds the idea step by step from first principles to the finished mechanism.

ElectroBOOM's Mehdi Sadaghdar explains how a full bridge rectifier works, the building block of AC to DC converters, with his usual humor and a demonstration of the circuit.

In this first Crust of Rust episode, Jon Gjengset live-codes an example that needs multiple explicit lifetime annotations. Along the way he covers string types and generics over a custom trait.

British Museum curator Irving Finkel teaches how to write cuneiform, with a colleague following along. It is a short, lively introduction to the script.

A step-by-step guide to building a lifter, a small triangular ionocraft made from balsa wood, aluminum foil and thin wire, powered by a high-voltage supply. It also shows high-voltage safety practices.

A beginner-focused tutorial on freehand knife sharpening with a single stone, aiming for a shaving-sharp edge in about five minutes.

Kristy Viers demonstrates the iPhone Magnifier combined with VoiceOver to describe the user's surroundings. She shows how the built-in feature reports scenes, faces and lighting.

DIY Perks shows how to turn old or smashed TVs and monitors into realistic artificial window lights, using the backlight and Fresnel lens to simulate distant daylight.

A University of Michigan Medicine demonstration of building a cheap DIY air purifier from a box fan and a HEPA or high-MERV filter using hardware-store parts. It explains why this helps against dust, smoke and viruses and ties it to local air quality readings.

A 1953 US Navy training film on the basic mechanisms in fire control computers: shafts, gears, cams and differentials. It shows how these mechanical parts compute ship and target firing solutions.

The first episode of Google's Machine Learning Recipes series. It introduces machine learning and builds a first supervised-learning classifier in about six lines of Python using scikit-learn.

The trailer for Tim Hunkin's series The Secret Life of Components, eight guides to mechanical and electromechanical parts for designers and makers.

Big Clive gives a 38-minute beginner's guide to identifying common electronic components and what they do. He keeps the maths minimal and aims to fill gaps for people just starting out.

Terry Moore's three-minute TED talk showing a better way to tie shoes, replacing the common granny knot with a square knot so laces stay tied.

The first part of Robert Baruch's series on building a 6800 CPU on an FPGA with nMigen, a Python-based hardware description language. It introduces the HDL while implementing a simpler 6800 core.

Jon Gjengset's long live-coding stream explains Rust's Pin and Unpin types: why they exist, how they work, and how they connect to futures and async/await. It also covers moving from pre-pinning code to the new model.

The first of a short series by Welch Labs on building a complete neural network in Python. It introduces the data and the architecture of a simple network before later parts cover forward propagation, gradient descent, and backpropagation.

David Sanders gives the first part of a two-part introduction to the Julia programming language at SciPy 2014. It walks through the language's basics and its appeal for scientific computing.

Andreas Spiess explains the basic principles of LoRa and LoRaWAN, their pros and cons, link budget and bandwidth. He shows his own gateway and client sending a message to The Things Network.

A guide to charging a non-Tesla EV, here a BMW i4, at a Tesla Supercharger in the UK, with do's and don'ts. It shows the process in practice now that the network is open to all cars.

LifebyMikeG lists 15 common mistakes beginner sourdough bakers make, with advice on fixing sticky, wet dough and other issues.

Jacques Pepin demonstrates deboning a whole chicken, quickly and with complete control. It is a short, wordless-feeling technique demo that shows a skill most cooks never learn.

A short, nearly wordless demonstration of making sourdough pizza at home using a cast iron pan and the oven. It shows a Neapolitan-style result without a pizza steel or stone.

A short, sweary cooking video in which Nat makes a quick bolognese using simple pantry ingredients. It is part of his isolation-era cooking series.

Russ Cox gives a 23-minute tour of the Acme text editor from Plan 9, showing its mouse-driven interface, executing commands from text, and its filesystem-based interface to other programs.

Dean Friedman's near-hour-long introduction to synthesis, covering the building blocks of sound and the controls on a synthesizer. He slowly adjusts knobs so viewers hear what each parameter does.

First of a three-part tutorial series on the i3 tiling window manager for Linux. It explains what i3 is, how to install it on Ubuntu, and how to use it.

Ben Krasnow of Applied Science explains how electrophoretic e-paper displays work and how he modified the driver firmware and waveform lookup tables of a 4.2-inch panel to reach roughly 3Hz partial refresh. It covers the tweakable constants in the refresh process and touches on colored e-ink microcapsules.

Jim Pavloff rebuilds the Prodigy track Smack My Bitch Up in Ableton, identifying the samples used and recreating the track by hand.

John Scholes builds a depth-first tree-search operator step by step in a Dyalog APL session. It covers higher-order functions and runs the search on the N-Queens problem.

In this American Masters clip, Jacques Pepin shows two different techniques for making a perfect omelet, a dish he is famous for teaching America.

Anders Brownworth gives a basic visual introduction to blockchain using an interactive web demo, covering SHA256 hashes, blocks, chains, distribution, tokens and coinbase transactions.

Ian Hubert shows how to use Blender's motion tracking to turn ordinary footage of a room into a stylized digital environment for an indie film. It is a quick, practical walkthrough in his loose, lazy-tutorial style.

David Beazley's workshop screencast builds asynchronous programming in Python from scratch, starting from callbacks and continuations and replacing threads to show how concurrency works underneath.

Harry Schwartz gives a roughly hour-long tour of Emacs Org mode as an outliner, task manager, markup language and agenda tool. He demonstrates how he uses it for documents, presentations and todo lists.

The first part of a series on programming in Jai, Jonathan Blow's in-development language. It covers compiling, writing hello world and using code from other files.

Lock-picking YouTuber Bill Johnson (BosnianBill) explains how to choose a high-security lock and why, showing examples and comparing designs. It covers what makes some padlocks more pick-resistant than others.

Andrej Karpathy builds a bigram character-level language model from scratch, introducing torch.Tensor and the framework of training, sampling and loss evaluation. It is the first step toward a GPT-style Transformer in his makemore series.

Markus Triska tours Prolog's most distinctive features, including its use as a database and query language, rule processing, constraint solving and compile-time rewriting. It also covers concise meta-interpreters.

Marco Baringer's tutorial video on SLIME, the Emacs mode for developing Common Lisp. It demonstrates the interactive workflow of working against a live Lisp image.