201 websites that teach you something

Fly out through our stellar neighbourhood, one star at a time

Slide tiles, double numbers, lose an hour to one more go

Windows 98 rebuilt in JavaScript, down to the fonts

One space image a day, explained by a working astronomer

Three rules are all a flock of birds needs

The chatbot that made everyone else build a chatbot

Anthropic's assistant, strongest on long documents

Four rules, and cells that build spaceships anyway

A 1996 US campaign website, preserved exactly as it was

Flood the whole board with one colour in thirty moves

The planet's wind, drawn as one continuous flowing sheet

Six thousand music genres, plotted on one scrollable map

Google's model, wired into search and your files

Two chemicals, two dials, and every pattern in nature

One word answers physics' most alarming question

Measure your reaction time against millions of strangers

The flight tracker that filters nothing out of the sky

Type your address, watch it drift 750 million years

Two anonymous models answer, you pick the winner

Weather radar, counting the birds that migrate overnight

Click a grid of squares and it becomes a melody

A graphing calculator that keeps up with your typing

Build a circuit and watch the electrons move through it

Name three bands you like and it guesses the fourth

A search engine that only returns actual datasets

When the space station crosses your sky, to the second

Today, then the month, then the epoch, then everything

A calendar of everything visible from where you live

Every classic Mac OS, booting in seconds, discs included

A ZX Spectrum in your browser, loading noise included

Endless chess tactics drawn from real losing positions

Start with four elements, end with 700-odd absurd ones

One long essay a day, on the questions without answers

The sky atlas professional astronomers use, in a tab

Browse by genre, mood, decade or who played on it

Machines taken apart in animation, layer by layer

Which asteroids would pay for the trip out to reach them

Filter by genre, format and location, then simply listen

A chiptune sequencer that fits a whole song in a URL

The etymology and history of first names, worldwide

Maths taught as intuition first, notation afterwards

An 1847 geometry book where colour replaces the labels

A world map where every pin is a field recording

Sixteen words, four secret groups, four mistakes allowed

Watch one nest from first egg to first flight

A weekly note listing five datasets you can have

Same six panels every time, different conversation

Search the sky the way the ESA science archives see it

Build a jointed creature and let it learn to walk

One statistics concept per page, all of it draggable

A briefing of progress you almost certainly missed

Learn CSS flexbox by getting frogs onto lily pads

Legally free music, curated rather than simply dumped

Answer a question, fund ten grains of rice

Classify a galaxy nobody has ever properly looked at

Hans Rosling's bubble chart, still worth an hour

Random two-wheeled cars, bred over generations, on hills

Industrial fishing effort, drawn as tracks across the sea

Satellite alerts wherever tree cover vanished this week

The Sun in every wavelength, going back fifteen years

Grant Sanderson's maths lessons, with the visuals inline

Everything about the curve behind every vector graphic

Read tomorrow's physics papers before they're published

A guidebook to the places no guidebook mentions

The best interactive explainers anyone is making

Every natural history book, scanned by the world's museums

The American statistical record, queryable directly

Play with the models behind epidemics, flocks and chaos

What happens between typing a command and seeing output

A hundred thousand old maps, zoomable to the street

Full-text search across thousands of old shareware discs

A catalogue of very nearly every record ever pressed

Machine learning papers you can actually see working

A pre-Wikipedia wiki where the writing is the point

A hub for every explainer you can play with

Nathan Yau on what the numbers are doing to us

A treemap of what people die of, by country and year

India's national collections, digitised into one place

Millions of scanned books, magazines and old manuals

One properly hard maths puzzle, every single month

The open half of the library everyone else pays for

The footnoted origin story of every image you have seen