3Blue1Brown
3blue1brown.com
Visual mathematics videos and interactive lessons that build genuine intuition for complex topics.
3Blue1Brown is Grant Sanderson's collection of maths lessons built around animation. The site organises the videos by topic, including linear algebra, calculus, differential equations, neural networks, probability, topology and number theory, so you can follow a series from start to finish.
The approach focuses on visual intuition: seeing why a result is true before working through the formulas. The site also links to the mailing list and to Patreon, which supports the work. It suits students, programmers and curious adults who found maths dull in school and want a different way in.
Why it is useful
Grant Sanderson approach to mathematical visualization has changed how many people understand topics like linear algebra and neural networks. The interactive lessons on the website go beyond the videos, letting you manipulate concepts directly.
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