code density

CGP Grey explains that postal codes are routing instructions for mail rather than geographic regions. He looks at the quirks and problems this causes.

3Blue1Brown's discovery-oriented introduction to error correction codes, building up Hamming codes from the puzzle of locating a flipped bit. It explains the parity-check idea and why it is so efficient.

Veritasium builds a QR code by hand to explain how it works. It covers the history of Morse code and barcodes, how QR codes encode data, why damaged codes still scan, and how safe they are.

8-Bit Show And Tell walks through the BASIC source code of the original Commodore 64 Sid Meier's Pirates!. It covers bugs, quirks and traces of abandoned features and scenarios left in the code.

Matthias Wandel tests old and new code on a range of PCs, including a new mini PC, to measure how much faster modern hardware really is. He also shows optimization techniques such as branchless code, with benchmark programs on GitHub.

CGP Grey explains why airport codes are inconsistent and sometimes confusing, from their origins in old weather station codes to the quirks that cause mistakes. He builds the story around a single typo that sent a flight to the wrong continent.

Matt Parker follows the community effort to speed up his slow Wordle-solving code, which ended up running hundreds of millions of times faster. He walks through the techniques contributors used.

CodeParade's short devlog on how spherical geometry looks in 2D and 3D and why it feels so unusual, part of the Hyperbolica series on a non-Euclidean game.

Kaze Emanuar explains how he rewrote and optimized the Super Mario 64 source code so it runs far faster on real N64 hardware. He covers performance bottlenecks and fixes in detail for his ROM hacks.

Oh The Urbanity! argues that most city dwellers live in dense residential neighbourhoods outside downtown, which can be calm and peaceful. It draws on older, denser parts of Toronto and Montreal.

Not Just Bikes takes on the common excuse that a country is simply too big or spread out for good transit and walkable cities. The video argues that city density and short everyday trips matter, not national size or overall population density.

About Here explains how North American building codes requiring two staircases make small multi-story apartment buildings hard to build, and contrasts this with places that allow single-stair designs.

Not Just Bikes contrasts traditional and suburban development in North America. It looks at the financials behind each pattern and argues that suburban development leaves cities unable to pay for their own infrastructure.

Not Just Bikes explains why living in a dense, bikeable Dutch city sharply reduced his family's environmental footprint and improved quality of life. It is a collaboration that continues on Climate Town.

Not Just Bikes explains missing middle housing, such as duplexes, townhouses and small apartment buildings. The video argues that zoning in the US and Canada has made these options almost illegal.

Not Just Bikes explains the Strong Towns argument that car-dependent American suburbs cost more to maintain than they generate in taxes. It describes the growth Ponzi scheme that props up municipal finances.

The first video in Not Just Bikes' Strong Towns series explains the financial instability of North American cities, based on Strong Towns research. It argues that low-density suburban growth costs more to maintain than it brings in.

Climate Town gives a comedic, fast-paced account of how the plastics industry promoted recycling, including the resin-code recycling symbol, while knowing most plastic could not be economically recycled. It points viewers to the Frontline documentary Plastic Wars for a deeper treatment.

Polylog explains how algorithms can be turned into circuits and encoded as satisfiability problems, which lets you effectively run them backwards. It uses this to motivate breaking RSA, general reductions to SAT, and what P vs NP is really asking.

A step-by-step animated explanation of how SHA-256 works, from padding and message schedule to the compression function and final hash, with source code for the animations.

Benn Jordan's video about storing a PNG image in a living bird, a starling that learns to reproduce encoded sounds. It mixes ornithology, audio engineering, and data encoding.

Not Just Bikes explains that car-dependent suburbs are not the only option, using Toronto's Riverdale as an example of a pre-war streetcar suburb. These walkable neighborhoods are popular but are now effectively illegal to build.

Kurzgesagt explores the idea that black holes could create universes and that we might live inside one. It builds up the physics of how density falls as black holes get larger.

A guest video by Welch Labs on 3Blue1Brown explaining how text-to-image and video models work. It covers CLIP, shared embedding spaces, diffusion models (DDPM, DDIM), conditioning, guidance and negative prompts.