Hacker News Reader

The python programs he wrote to produce those visualizations is also hosted on GitHub[0]. The repo includes the source for all his videos.

[0] https://github.com/3b1b/manim

for the lazy https://www.youtube.com/channel/UCYO_jab_esuFRV4b17AJtAw

His linear algebra series is fantastic study material in helping poeple to picture just exactly what a linear transformation/determinant/eigenvalue looks like!