As part of developing his Youtube channel, he has written and open-sourced manim, a library for programatically generating animations written in Python: https://github.com/ManimCommunity/manim/.
And for anyone wondering where the name 3blue1brown comes from: Grant Sanderson has a condition called heterochromia, his right eye is 3 parts blue, and 1 part brown, like his logo.
I wonder how this is resolved for places that ask for eye color (various people identification registries). If the information could be accurate and understandable (from a short database column entry), it's a quite unique identifier.
Heterochromia of the eye is called heterochromia iridum or heterochromia iridis. It can be complete or sectoral. In complete heterochromia, one iris is a different color from the other. In sectoral heterochromia, part of one iris is a different color from its remainder. In central heterochromia, there is a ring around the pupil or possibly spikes of different colors radiating from the pupil.
So, in case of Grant Sanderson, it would be sectoral heterochromia.
He also has started a podcast this year. In each episode he discusses mainly math and education related topics with different people. I have liked it quite much.
The videos on linear algebra in particular are worth it, especially if you do any sort of machine learning: https://www.youtube.com/watch?v=fNk_zzaMoSs.
The author of the channel is Grant Sanderson. He has recently given a talk at SIGGRAPH 2021: https://www.youtube.com/watch?v=gvck7ssg9dE.
As part of developing his Youtube channel, he has written and open-sourced manim, a library for programatically generating animations written in Python: https://github.com/ManimCommunity/manim/.