Mathematics

Animated series that build calculus, linear algebra, Fourier analysis and neural networks up from visual intuition before any symbol appears. Watch rather than click, but few things explain better.

Type a function and it appears instantly; wrap any constant in a slider and drag it to watch the curve respond. The tightest feedback loop between algebra and shape available in a browser.

Geometry, algebra, calculus, statistics and 3D sharing one canvas, where every object stays linked to its construction. Move a point and everything built from it moves too.

A complete linear algebra textbook in which every single figure is interactive. Vectors, bases, determinants and eigenvalues become things you drag rather than things you take on trust.

An interactive textbook you poke rather than read: the text waits for you to drag, sort or fold something before it continues. Covers geometry, graph theory, probability and more, and includes Polypad's manipulatives.

A visual introduction to probability and statistics where every distribution, estimator and regression line is a live diagram you perturb. The clearest treatment of sampling and inference on the open web.

Short single-idea visual explanations — eigenvectors, Markov chains, conditional probability, principal component analysis. Each is one page and one interactive figure, and each lands.

Thousands of small parameterised demonstrations across maths, physics and engineering, each contributed by someone who needed exactly that diagram. Uneven, but the coverage is enormous.